1
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Kooij B, Chen DW, Fadaei-Tirani F, Severin K. Metal-Mediated Synthesis of a Mixed Arduengo-Fischer Carbodicarbene Ligand. Angew Chem Int Ed Engl 2024; 63:e202407945. [PMID: 38856098 DOI: 10.1002/anie.202407945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Revised: 06/04/2024] [Accepted: 06/10/2024] [Indexed: 06/11/2024]
Abstract
Carbodicarbenes are strong C-donor ligands, which have found numerous applications in organometallic and main group element chemistry. Herein, we report a structurally distinct carbodicarbene ligand, which is formed by dinitrogenative coupling of a Fischer carbene complex with an N-heterocyclic diazoolefin. The resulting carbonyl complex serves as a stable source for the mixed Arduengo-Fischer carbodicarbene ligand. Facile ligand transfer reactions were demonstrated to occur with gold(I), copper(I), palladium(II), and rhodium(I) complexes.
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Affiliation(s)
- Bastiaan Kooij
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Damien W Chen
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Farzaneh Fadaei-Tirani
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Kay Severin
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
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2
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Hu L, Chakraborty S, Tumanov N, Wouters J, Robiette R, Berionni G. Regulating iminophosphorane PN bond reactivity through geometric constraints with cage-shaped triarylphosphines. Chem Commun (Camb) 2024; 60:7073-7076. [PMID: 38888188 DOI: 10.1039/d4cc01868k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Abstract
Structure-reactivity investigations and quantum-chemical parametrization of steric and electronic properties of geometrically constrained iminophosphoranes enabled the design of new frustrated Lewis pairs and revealed unusual properties at the phosphonium center embedded in the cage-shaped triptycene tricyclic scaffold.
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Affiliation(s)
- Lei Hu
- Université de Namur, Department of Chemistry, Namur Institute of Structured Matter (NISM), Rue de Bruxelles 61, Namur 5000, Belgium.
- Université Catholique de Louvain, Institute of Condensed Matter and Nanosciences, Place Louis Pasteur 1 box L4.01.02, Louvain-la-Neuve 1348, Belgium.
| | - Sayandip Chakraborty
- Université de Namur, Department of Chemistry, Namur Institute of Structured Matter (NISM), Rue de Bruxelles 61, Namur 5000, Belgium.
| | - Nikolay Tumanov
- Université de Namur, Department of Chemistry, Namur Institute of Structured Matter (NISM), Rue de Bruxelles 61, Namur 5000, Belgium.
| | - Johan Wouters
- Université de Namur, Department of Chemistry, Namur Institute of Structured Matter (NISM), Rue de Bruxelles 61, Namur 5000, Belgium.
| | - Raphaël Robiette
- Université Catholique de Louvain, Institute of Condensed Matter and Nanosciences, Place Louis Pasteur 1 box L4.01.02, Louvain-la-Neuve 1348, Belgium.
| | - Guillaume Berionni
- Université de Namur, Department of Chemistry, Namur Institute of Structured Matter (NISM), Rue de Bruxelles 61, Namur 5000, Belgium.
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3
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Obi AD, Deng CL, Alexis AJ, Dickie DA, Gilliard RJ. Geminal bimetallic coordination of a carbone to main-group and transition metals. Chem Commun (Camb) 2024. [PMID: 38284335 DOI: 10.1039/d3cc06226k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2024]
Abstract
The non-bonding carbone lone pair in geometrically-constrained antimony and bismuth carbodiphosphorane complexes readily complexed AuCl to afford rare examples of geminal bimetallic carbone coordination featuring a main-group metal.
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Affiliation(s)
- Akachukwu D Obi
- Department of Chemistry, University of Virginia, 409 McCormick Road, PO Box 400319, Charlottesville, Virginia, 22904, USA
| | - Chun-Lin Deng
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Building 18-596, Cambridge, MA 02139-4307, USA.
| | - Andrew J Alexis
- Department of Chemistry, University of Virginia, 409 McCormick Road, PO Box 400319, Charlottesville, Virginia, 22904, USA
| | - Diane A Dickie
- Department of Chemistry, University of Virginia, 409 McCormick Road, PO Box 400319, Charlottesville, Virginia, 22904, USA
| | - Robert J Gilliard
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Building 18-596, Cambridge, MA 02139-4307, USA.
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4
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Janda BA, Tran JA, Chang DK, Nerhood GC, Maduka Ogba O, Liberman-Martin AL. Carbodiimide and Isocyanate Hydroboration by a Cyclic Carbodiphosphorane Catalyst. Chemistry 2024; 30:e202303095. [PMID: 37847813 DOI: 10.1002/chem.202303095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 10/13/2023] [Accepted: 10/17/2023] [Indexed: 10/19/2023]
Abstract
We report hydroboration of carbodiimide and isocyanate substrates catalyzed by a cyclic carbodiphosphorane catalyst. The cyclic carbodiphosphorane outperformed the other Lewis basic carbon species tested, including other zerovalent carbon compounds, phosphorus ylides, an N-heterocyclic carbene, and an N-heterocyclic olefin. Hydroborations of seven carbodiimides and nine isocyanates were performed at room temperature to form N-boryl formamidine and N-boryl formamide products. Intermolecular competition experiments demonstrated the selective hydroboration of alkyl isocyanates over carbodiimide and ketone substrates. DFT calculations support a proposed mechanism involving activation of pinacolborane by the carbodiphosphorane catalyst, followed by hydride transfer and B-N bond formation.
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Affiliation(s)
- Ben A Janda
- Chemistry and Biochemistry Program, Schmid College of Science and Technology, Chapman University, 450 North Center Street, Orange, CA 92866, USA
| | - Julie A Tran
- Chemistry and Biochemistry Program, Schmid College of Science and Technology, Chapman University, 450 North Center Street, Orange, CA 92866, USA
| | - Daniel K Chang
- Chemistry and Biochemistry Program, Schmid College of Science and Technology, Chapman University, 450 North Center Street, Orange, CA 92866, USA
| | - Gabriela C Nerhood
- Chemistry and Biochemistry Program, Schmid College of Science and Technology, Chapman University, 450 North Center Street, Orange, CA 92866, USA
| | - O Maduka Ogba
- Chemistry and Biochemistry Program, Schmid College of Science and Technology, Chapman University, 450 North Center Street, Orange, CA 92866, USA
| | - Allegra L Liberman-Martin
- Chemistry and Biochemistry Program, Schmid College of Science and Technology, Chapman University, 450 North Center Street, Orange, CA 92866, USA
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5
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Baker CF, Seed JA, Adams RW, Lee D, Liddle ST. 13C carbene nuclear magnetic resonance chemical shift analysis confirms Ce IV[double bond, length as m-dash]C double bonding in cerium(iv)-diphosphonioalkylidene complexes. Chem Sci 2023; 15:238-249. [PMID: 38131084 PMCID: PMC10732143 DOI: 10.1039/d3sc04449a] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 11/27/2023] [Indexed: 12/23/2023] Open
Abstract
Diphosphonioalkylidene dianions have emerged as highly effective ligands for lanthanide and actinide ions, and the resulting formal metal-carbon double bonds have challenged and developed conventional thinking about f-element bond multiplicity and covalency. However, f-element-diphosphonioalkylidene complexes can be represented by several resonance forms that render their metal-carbon double bond status unclear. Here, we report an experimentally-validated 13C Nuclear Magnetic Resonance computational assessment of two cerium(iv)-diphosphonioalkylidene complexes, [Ce(BIPMTMS)(ODipp)2] (1, BIPMTMS = {C(PPh2NSiMe3)2}2-; Dipp = 2,6-diisopropylphenyl) and [Ce(BIPMTMS)2] (2). Decomposing the experimental alkylidene chemical shifts into their corresponding calculated shielding (σ) tensor components verifies that these complexes exhibit Ce[double bond, length as m-dash]C double bonds. Strong magnetic coupling of Ce[double bond, length as m-dash]C σ/π* and π/σ* orbitals produces strongly deshielded σ11 values, a characteristic hallmark of alkylidenes, and the largest 13C chemical shift tensor spans of any alkylidene complex to date (1, 801 ppm; 2, 810 ppm). In contrast, the phosphonium-substituent shielding contributions are much smaller than the Ce[double bond, length as m-dash]C σ- and π-bond components. This study confirms significant Ce 4f-orbital contributions to the Ce[double bond, length as m-dash]C bonding, provides further support for a previously proposed inverse-trans-influence in 2, and reveals variance in the 4f spin-orbit contributions that relate to the alkylidene hybridisation. This work thus confirms the metal-carbon double bond credentials of f-element-diphosphonioalkylidenes, providing quantified benchmarks for understanding diphosphonioalkylidene bonding generally.
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Affiliation(s)
- Cameron F Baker
- Department of Chemistry, The University of Manchester Oxford Road Manchester M13 9PL UK
| | - John A Seed
- Department of Chemistry, The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Ralph W Adams
- Department of Chemistry, The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Daniel Lee
- Department of Chemical Engineering, The University of Manchester Oxford Road Manchester M13 9PL UK
| | - Stephen T Liddle
- Department of Chemistry, The University of Manchester Oxford Road Manchester M13 9PL UK
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6
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Yu CH, Au-Yeung KC, Liu R, Lee CH, Jiang D, Semagne Aweke B, Wu CH, Wang YJ, Wang TH, Voon Kong K, Yap GPA, Chen WC, Frenking G, Zhao L, Ong TG. Diversification of the Carbodicarbene Class by Embedding an Anionic Component in its Scaffold. Chemistry 2023; 29:e202302886. [PMID: 37730960 DOI: 10.1002/chem.202302886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/19/2023] [Accepted: 09/19/2023] [Indexed: 09/22/2023]
Abstract
Carbodicarbene (CDC) has become an emerging ligand in many fields due to its strong σ-donating ability.
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Affiliation(s)
- Cheng-Han Yu
- Institute of chemistry, Academia Sinica, Taipei, Taiwan (R.O.C., 115201
| | - Ka-Chun Au-Yeung
- Institute of chemistry, Academia Sinica, Taipei, Taiwan (R.O.C., 115201
- Corporate R&D Center, LCY Chemical Corporation, Kaohsiung, Taiwan (R.O.C
| | - Ruiqin Liu
- School of Chemistry and Molecular Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China
| | - Chao-Hsien Lee
- Institute of chemistry, Academia Sinica, Taipei, Taiwan (R.O.C., 115201
| | - Dandan Jiang
- School of Chemistry and Molecular Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China
| | - Bamlaku Semagne Aweke
- Institute of chemistry, Academia Sinica, Taipei, Taiwan (R.O.C., 115201
- Department of Applied Chemistry, National Yang Ming Chiao Tung University, Hsinchu, Taiwan (R.O.C
- Sustainable Chemical Science and Technology, Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan (R.O.C
| | - Chia-Hung Wu
- Institute of chemistry, Academia Sinica, Taipei, Taiwan (R.O.C., 115201
- Department of Chemistry, National Taiwan University, Taipei, Taiwan (R.O.C
| | - Yu-Jou Wang
- Institute of chemistry, Academia Sinica, Taipei, Taiwan (R.O.C., 115201
- Department of Chemistry, National Taiwan University, Taipei, Taiwan (R.O.C
| | - Ting-Hsuan Wang
- Institute of chemistry, Academia Sinica, Taipei, Taiwan (R.O.C., 115201
| | - Kien Voon Kong
- Department of Chemistry, National Taiwan University, Taipei, Taiwan (R.O.C
| | - Glenn P A Yap
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware, United States
| | - Wen-Ching Chen
- Institute of chemistry, Academia Sinica, Taipei, Taiwan (R.O.C., 115201
| | - Gernot Frenking
- School of Chemistry and Molecular Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, D-35043, Marburg, Germany
| | - Lili Zhao
- School of Chemistry and Molecular Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China
| | - Tiow-Gan Ong
- Institute of chemistry, Academia Sinica, Taipei, Taiwan (R.O.C., 115201
- Department of Chemistry, National Taiwan University, Taipei, Taiwan (R.O.C
- Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung, Taiwan (R.O.C
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7
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Tannoux T, Mazaud L, Cheisson T, Casaretto N, Auffrant A. Fe II complexes supported by an iminophosphorane ligand: synthesis and reactivity. Dalton Trans 2023; 52:12010-12019. [PMID: 37581245 DOI: 10.1039/d3dt00950e] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/16/2023]
Abstract
The synthesis of iron complexes supported by a mixed phosphine-lutidine-iminophosphorane (PPyNP) ligand was carried out. While bidentate κ2-N,N coordination was observed for FeCl2, pincer coordination modes were adopted at cationic iron centers, either through dechlorination of [LFe(PPyNP)Cl2] (1) or direct coordination of PPyNP to Fe(OTf)2. Reaction with tert-butylisocyanide gave access to the diamagnetic octahedral complex [Fe(PPyNP)(CNtBu)3]X2 (X = OTf (4), Cl (4')). Both 1 and 4 were shown to undergo deprotonation of the phosphinomethyl group, but the resulting complexes were not active for the dehydrogenative coupling of hexan-1-ol. The hydrosilylation of acetophenones was catalyzed at room temperature with 1 mol% of a catalyst generated in situ from cationic PPyNP-supported iron triflate complexes and KHBEt3.
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Affiliation(s)
- Thibault Tannoux
- Laboratoire de Chimie Moléculaire (LCM) CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, Route de Saclay, F-91120 Palaiseau Cedex, France.
| | - Louis Mazaud
- Laboratoire de Chimie Moléculaire (LCM) CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, Route de Saclay, F-91120 Palaiseau Cedex, France.
| | - Thibault Cheisson
- Laboratoire de Chimie Moléculaire (LCM) CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, Route de Saclay, F-91120 Palaiseau Cedex, France.
| | - Nicolas Casaretto
- Laboratoire de Chimie Moléculaire (LCM) CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, Route de Saclay, F-91120 Palaiseau Cedex, France.
| | - Audrey Auffrant
- Laboratoire de Chimie Moléculaire (LCM) CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, Route de Saclay, F-91120 Palaiseau Cedex, France.
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8
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Hansmann MM. Diazoalkenes: From an Elusive Intermediate to a Stable Substance Class in Organic Chemistry. Angew Chem Int Ed Engl 2023; 62:e202304574. [PMID: 37095063 DOI: 10.1002/anie.202304574] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 04/22/2023] [Accepted: 04/24/2023] [Indexed: 04/26/2023]
Abstract
Over decades diazoalkenes (R2 C=C=N2 ) were postulated as reactive intermediates in organic chemistry even though their direct spectroscopic detection proved very challenging. In the 1970/80ies several groups probed their existence mainly indirectly by trapping experiments or directly by matrix-isolation studies. In 2021, our group and the Severin group reported independently the synthesis and characterization of the first room-temperature stable diazoalkenes, which initiated a rapidly expanding research field. Up to now four different classes of N-heterocyclic substituted room-temperature stable diazoalkenes have been reported. Their properties and unique reactivity, such as N2 /CO exchange or utilization as vinylidene precursors in organic and transition metal chemistry are presented. This review summarizes the early discoveries of diazoalkenes from their initial postulation as transient, elusive species up to the recent findings of the room-temperature stable derivatives.
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Affiliation(s)
- Max M Hansmann
- Technische Universität Dortmund, Fakultät für Chemie und Chemische Biologie, Otto-Hahn-Str. 6, Dortmund, Germany
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9
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Kooij B, Dong Z, Fadaei-Tirani F, Scopelliti R, Severin K. Synthesis and Reactivity of an Anionic Diazoolefin. Angew Chem Int Ed Engl 2023; 62:e202308625. [PMID: 37387555 DOI: 10.1002/anie.202308625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 06/28/2023] [Accepted: 06/30/2023] [Indexed: 07/01/2023]
Abstract
Bent (hetero)allenes such as carbodicarbenes and carbodiphosphoranes can act as neutral C-donor ligands, and diverse applications in coordination chemistry have been reported. N-Heterocyclic diazoolefins are heterocumulenes, which can function in a similar fashion as L-type ligands. Herein, we describe the synthesis and the reactivity of an anionic diazoolefin. This compound displays distinct reactivity compared to neutral diazoolefins, as evidenced by the preparation of diazo compounds via protonation, alkylation, or silylation. The anionic diazoolefin can be employed as an ambidentate, X-type ligand in salt metathesis reactions with metal halide complexes. Extrusion of dinitrogen was observed in a reaction with PCl(NiPr2 )2 , resulting in a stable phosphinocarbene.
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Affiliation(s)
- Bastiaan Kooij
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Zhaowen Dong
- Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, 610064, Chengdu, P. R. China
| | - Farzaneh Fadaei-Tirani
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Rosario Scopelliti
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Kay Severin
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
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10
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Authesserre U, Swamy VSVSN, Saffon-Merceron N, Baceiredo A, Kato T, Maerten E. New Insight into the Reactivity of S,S-Bis-ylide. Molecules 2023; 28:molecules28083295. [PMID: 37110528 PMCID: PMC10142965 DOI: 10.3390/molecules28083295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 04/04/2023] [Accepted: 04/06/2023] [Indexed: 04/29/2023] Open
Abstract
The present work focuses on the reactivity of S,S-bis-ylide 2, which presents a strong nucleophilic character, as evidenced by reactions with methyl iodide and CO2, affording C-methylated salts 3 and betaine 4, respectively. The derivatization of betaine 4 affords the corresponding ester derivative 6, which is fully characterized by using NMR spectroscopy and X-ray diffraction analysis. Furthermore, an original reaction with phosphenium ions leads to the formation of a transient push-pull phosphino(sulfonio)carbene 8, which rearranges to give stabilized sulfonium ylide derivative 7.
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Affiliation(s)
- Ugo Authesserre
- Université de Toulouse, UPS, and CNRS, LHFA UMR 5069, 118 Route de Narbonne, 31062 Toulouse, France
| | - V S V S N Swamy
- Université de Toulouse, UPS, and CNRS, LHFA UMR 5069, 118 Route de Narbonne, 31062 Toulouse, France
| | - Nathalie Saffon-Merceron
- Université de Toulouse, UPS, and CNRS, ICT UAR2599 118 Route de Narbonne, 31062 Toulouse, France
| | - Antoine Baceiredo
- Université de Toulouse, UPS, and CNRS, LHFA UMR 5069, 118 Route de Narbonne, 31062 Toulouse, France
| | - Tsuyoshi Kato
- Université de Toulouse, UPS, and CNRS, LHFA UMR 5069, 118 Route de Narbonne, 31062 Toulouse, France
| | - Eddy Maerten
- Université de Toulouse, UPS, and CNRS, LHFA UMR 5069, 118 Route de Narbonne, 31062 Toulouse, France
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11
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Popovici I, Barthes C, Tannoux T, Duhayon C, Casaretto N, Monari A, Auffrant A, Canac Y. Phosphonium Ylides vs Iminophosphoranes: The Role of the Coordinating Ylidic Atom in cis-[Phosphine-Ylide Rh(CO) 2] Complexes. Inorg Chem 2023; 62:2376-2388. [PMID: 36704899 DOI: 10.1021/acs.inorgchem.2c04151] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The coordinating properties of two families of ylides, namely, phosphonium ylides and iminophosphoranes, differently substituted at the ylidic center (CH2- vs NiPr-), have been investigated in structurally related cationic phosphine-ylide Rh(CO)2 complexes obtained from readily available phosphine-phosphonium salt precursors derived from an ortho-phenylene bridge. However, while the Rh(CO)2 complex bearing the P+-CH2- donor moiety proved to be stable, the P═NiPr donor end appeared to induce lability to one of the CO groups. All of the RhI carbonyl complexes in both ylide series were fully characterized, including through X-ray diffraction analysis. Based on the experimental and calculated infrared (IR) CO stretching frequencies in Rh(CO)2 complexes, we evidenced that the phosphonium ylide ligand is a stronger donor than the iminophosphorane ligand. However, we also found that the difference in the intrinsic electronic properties can be largely compensated by the introduction of an iPr substituent on the N atom of the iminophosphorane, hence pointing to the noninnocent role of the peripheral substituent and opening novel possibilities to tune the properties of metal complexes containing ylide ligands.
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Affiliation(s)
- Ingrid Popovici
- Laboratoire de Chimie Moléculaire (LCM), CNRS, École Polytechnique, Institut Polytechnique de Paris, Route de Saclay, 91120 Palaiseau, France
| | - Cécile Barthes
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse Cedex 4, France
| | - Thibault Tannoux
- Laboratoire de Chimie Moléculaire (LCM), CNRS, École Polytechnique, Institut Polytechnique de Paris, Route de Saclay, 91120 Palaiseau, France
| | - Carine Duhayon
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse Cedex 4, France
| | - Nicolas Casaretto
- Laboratoire de Chimie Moléculaire (LCM), CNRS, École Polytechnique, Institut Polytechnique de Paris, Route de Saclay, 91120 Palaiseau, France
| | - Antonio Monari
- ITODYS, Université Paris Cité and CNRS, F-75006 Paris, France
| | - Audrey Auffrant
- Laboratoire de Chimie Moléculaire (LCM), CNRS, École Polytechnique, Institut Polytechnique de Paris, Route de Saclay, 91120 Palaiseau, France
| | - Yves Canac
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse Cedex 4, France
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12
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Dolai R, Kumar R, Elvers BJ, Pal PK, Joseph B, Sikari R, Nayak MK, Maiti A, Singh T, Chrysochos N, Jayaraman A, Krummenacher I, Mondal J, Priyakumar UD, Braunschweig H, Yildiz CB, Schulzke C, Jana A. Carbodicarbenes and Striking Redox Transitions of their Conjugate Acids: Influence of NHC versus CAAC as Donor Substituents. Chemistry 2023; 29:e202202888. [PMID: 36129127 PMCID: PMC10100033 DOI: 10.1002/chem.202202888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Indexed: 01/11/2023]
Abstract
Herein, a new type of carbodicarbene (CDC) comprising two different classes of carbenes is reported; NHC and CAAC as donor substituents and compare the molecular structure and coordination to Au(I)Cl to those of NHC-only and CAAC-only analogues. The conjugate acids of these three CDCs exhibit notable redox properties. Their reactions with [NO][SbF6 ] were investigated. The reduction of the conjugate acid of CAAC-only based CDC with KC8 results in the formation of hydrogen abstracted/eliminated products, which proceed through a neutral radical intermediate, detected by EPR spectroscopy. In contrast, the reduction of conjugate acids of NHC-only and NHC/CAAC based CDCs led to intermolecular reductive (reversible) carbon-carbon sigma bond formation. The resulting relatively elongated carbon-carbon sigma bonds were found to be readily oxidized. They were, thus, demonstrated to be potent reducing agents, underlining their potential utility as organic electron donors and n-dopants in organic semiconductor molecules.
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Affiliation(s)
- Ramapada Dolai
- Tata Institute of Fundamental Research Hyderabad Gopanpally, Hyderabad, 500046, Telangana, India
| | - Rahul Kumar
- Tata Institute of Fundamental Research Hyderabad Gopanpally, Hyderabad, 500046, Telangana, India
| | - Benedict J Elvers
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Strasse 4, 17489, Greifswald, Germany
| | - Pradeep Kumar Pal
- International Institute of Information Technology Gachibowli, Hyderabad, 500032, India
| | - Benson Joseph
- Tata Institute of Fundamental Research Hyderabad Gopanpally, Hyderabad, 500046, Telangana, India
| | - Rina Sikari
- Tata Institute of Fundamental Research Hyderabad Gopanpally, Hyderabad, 500046, Telangana, India
| | - Mithilesh Kumar Nayak
- Tata Institute of Fundamental Research Hyderabad Gopanpally, Hyderabad, 500046, Telangana, India
| | - Avijit Maiti
- Tata Institute of Fundamental Research Hyderabad Gopanpally, Hyderabad, 500046, Telangana, India
| | - Tejender Singh
- Tata Institute of Fundamental Research Hyderabad Gopanpally, Hyderabad, 500046, Telangana, India
| | - Nicolas Chrysochos
- Tata Institute of Fundamental Research Hyderabad Gopanpally, Hyderabad, 500046, Telangana, India
| | - Arumugam Jayaraman
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Ivo Krummenacher
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Jagannath Mondal
- Tata Institute of Fundamental Research Hyderabad Gopanpally, Hyderabad, 500046, Telangana, India
| | - U Deva Priyakumar
- International Institute of Information Technology Gachibowli, Hyderabad, 500032, India
| | - Holger Braunschweig
- Institute of Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Cem B Yildiz
- Department of Aromatic and Medicinal Plants, Aksaray University, Aksaray, 68100, Turkey
| | - Carola Schulzke
- Institut für Biochemie, Universität Greifswald, Felix-Hausdorff-Strasse 4, 17489, Greifswald, Germany
| | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad Gopanpally, Hyderabad, 500046, Telangana, India
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13
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Tannoux T, Auffrant A. Complexes featuring tridentate iminophosphorane ligands: Synthesis, reactivity, and catalysis. Coord Chem Rev 2023. [DOI: 10.1016/j.ccr.2022.214845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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14
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Lui NM, MacMillan SN, Collum DB. Lithiated Oppolzer Enolates: Solution Structures, Mechanism of Alkylation, and Origin of Stereoselectivity. J Am Chem Soc 2022; 144:23379-23395. [PMID: 36534055 PMCID: PMC10071589 DOI: 10.1021/jacs.2c09341] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Camphorsultam-based lithium enolates referred to colloquially as Oppolzer enolates are examined spectroscopically, crystallographically, kinetically, and computationally to ascertain the mechanism of alkylation and the origin of the stereoselectivity. Solvent- and substrate-dependent structures include tetramers for alkyl-substituted enolates in toluene, unsymmetric dimers for aryl-substituted enolates in toluene, substrate-independent symmetric dimers in THF and THF/toluene mixtures, HMPA-bridged trisolvated dimers at low HMPA concentrations, and disolvated monomers for the aryl-substituted enolates at elevated HMPA concentrations. Extensive analyses of the stereochemistry of aggregation are included. Rate studies for reaction with allyl bromide implicate an HMPA-solvated ion pair with a +Li(HMPA)4 counterion. Dependencies on toluene and THF are attributed to exclusively secondary-shell (medium) effects. Aided by density functional theory (DFT) computations, a stereochemical model is presented in which neither chelates nor the lithium gegenion serves roles. The stereoselectivity stems from the chirality within the sultam ring and not the camphor skeletal core.
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Affiliation(s)
- Nathan M Lui
- Department of Chemistry and Chemical Biology Baker Laboratory, Cornell University Ithaca, New York 14853-1301, United States
| | - Samantha N MacMillan
- Department of Chemistry and Chemical Biology Baker Laboratory, Cornell University Ithaca, New York 14853-1301, United States
| | - David B Collum
- Department of Chemistry and Chemical Biology Baker Laboratory, Cornell University Ithaca, New York 14853-1301, United States
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15
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Burnett S, Bourne C, Slawin AMZ, van Mourik T, Stasch A. Umpolung of an Aliphatic Ketone to a Magnesium Ketone‐1,2‐diide Complex with Vicinal Dianionic Charge. Angew Chem Int Ed Engl 2022; 61:e202204472. [PMID: 35762819 PMCID: PMC9541192 DOI: 10.1002/anie.202204472] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Indexed: 12/05/2022]
Abstract
The new β‐diketimine iPrDipnacnacH, HC(iPrCNDip)2H, Dip=2,6‐iPr2‐C6H3, was converted to the magnesium(I) complex [{(iPrDipnacnac)Mg}2] and reaction with 2‐adamantanone (OAd) afforded the ketone‐1,2‐diide complex [{(iPrDipnacnac)Mg}2(μ‐OAd)]. The complex contains the first stable dianion of an aliphatic ketone with an electropositive metal and shows an OAd2− unit with long C−O bond and pyramidal carbon centre. DFT studies reveal an anionic charge on both neighbouring C and O atoms. Reductions of aliphatic ketones with magnesium(I) complexes show that these likely proceed via highly reactive dianions and afforded a 1 : 1 mixture of an alkoxide and an enolate when an enolisable ketone was used, and rapid CH activations reactions, e.g., of stabilising ligand moieties, when non‐enolisable ketones were employed.
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Affiliation(s)
- Stuart Burnett
- EaStCHEM School of Chemistry University of St Andrews North Haugh St Andrews KY16 9ST UK
| | - Connor Bourne
- EaStCHEM School of Chemistry University of St Andrews North Haugh St Andrews KY16 9ST UK
| | - Alexandra M. Z. Slawin
- EaStCHEM School of Chemistry University of St Andrews North Haugh St Andrews KY16 9ST UK
| | - Tanja van Mourik
- EaStCHEM School of Chemistry University of St Andrews North Haugh St Andrews KY16 9ST UK
| | - Andreas Stasch
- EaStCHEM School of Chemistry University of St Andrews North Haugh St Andrews KY16 9ST UK
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16
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Burnett S, Bourne C, Slawin AMZ, van Mourik T, Stasch A. Umpolung of an Aliphatic Ketone to a Magnesium Ketone‐1,2‐diide Complex with Vicinal Dianionic Charge. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202204472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Stuart Burnett
- University of St Andrews School of Chemistry School of Chemistry UNITED KINGDOM
| | - Connor Bourne
- University of St Andrews School of Chemistry School of Chemistry UNITED KINGDOM
| | | | - Tanja van Mourik
- University of St Andrews School of Chemistry School of Chemistry UNITED KINGDOM
| | - Andreas Stasch
- University of St Andrews School of Chemistry North Haugh KY169ST St Andrews UNITED KINGDOM
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17
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Moerman A, Sosa Carrizo ED, Théron B, Cattey H, Le Gendre P, Fleurat-Lessard P, Normand AT. Template Synthesis of NPN' Pincer-type Ligands at Titanium Using an Ambiphilic Phosphide Scaffold. Inorg Chem 2022; 61:7642-7653. [PMID: 35500277 DOI: 10.1021/acs.inorgchem.2c00917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Ti-imido complex [TiCl(NtBu)(BIPP)] [1; BIPP = bis(iminophosphoranyl)phosphide ligand] reacts with terminal alkynes R-C≡CH (R = phenyl, isopropenyl, cyclopropyl, and 2-pyridyl) via P-P bond cleavage of the BIPP ligand. The resulting complexes [TiCl(NPN')(NPhPPh2)] (2a-d) contain a pincer-type NPN' phosphide ligand that incorporates the terminal alkyne and the imido ligand from complex 1. Complexes 2a-d feature two chiral centers (Ti and P) with interdependent absolute configurations; thus, they are formed stereoselectively. Complex 2a (R = phenyl) undergoes chloride abstraction with [Et3SiHSiEt3][B(C6F5)4], yielding [Ti(NPN')(NPhPPh2)][B(C6F5)4] (3). Complex 3 is a moderately active and stereoselective initiator for the ring-opening polymerization of rac-lactide. Complex 3 activates the C═O bond of 4-iodobenzaldehyde to give complex 4 as a single diastereomer despite the presence of three chiral centers. Complex 3 undergoes transmetallation with SbCl3, yielding [Sb(NPN')][B(C6F5)4] (5) and [TiCl3(NPhPPh2)] (6) selectively. The bonding situation in 3 and 5 was analyzed using Bader's atoms in molecules and the electron localization function, showing that the nitrogen atoms of the NPN' ligand are electronically similar, and that the metal-phosphide interaction is more polar in the case of titanium.
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Affiliation(s)
- Alex Moerman
- Institut de Chimie Moléculaire de L'Université de Bourgogne (ICMUB), Université de Bourgogne, 9 Avenue Alain Savary, Dijon 21000, France
| | - E Daiann Sosa Carrizo
- Institut de Chimie Moléculaire de L'Université de Bourgogne (ICMUB), Université de Bourgogne, 9 Avenue Alain Savary, Dijon 21000, France
| | - Benjamin Théron
- Institut de Chimie Moléculaire de L'Université de Bourgogne (ICMUB), Université de Bourgogne, 9 Avenue Alain Savary, Dijon 21000, France
| | - Hélène Cattey
- Institut de Chimie Moléculaire de L'Université de Bourgogne (ICMUB), Université de Bourgogne, 9 Avenue Alain Savary, Dijon 21000, France
| | - Pierre Le Gendre
- Institut de Chimie Moléculaire de L'Université de Bourgogne (ICMUB), Université de Bourgogne, 9 Avenue Alain Savary, Dijon 21000, France
| | - Paul Fleurat-Lessard
- Institut de Chimie Moléculaire de L'Université de Bourgogne (ICMUB), Université de Bourgogne, 9 Avenue Alain Savary, Dijon 21000, France
| | - Adrien T Normand
- Institut de Chimie Moléculaire de L'Université de Bourgogne (ICMUB), Université de Bourgogne, 9 Avenue Alain Savary, Dijon 21000, France
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18
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Yadav R, Sinhababu S, Yadav R, Kundu S. Base-stabilized formally zero-valent mono and diatomic molecular main-group compounds. Dalton Trans 2022; 51:2170-2202. [PMID: 35040452 DOI: 10.1039/d1dt03569j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Various compounds are known for transition metals in their formal zero-oxidation state, while similar compounds of main-group elements are recently realized and limited to only a few examples. Lewis-base-stabilized mono and diatomic molecular species (B2, C, C2, Si, Si2, Ge, Ge2, Sn, P2, As2, Sb2) represent groundbreaking examples of main-group compounds with formally zero-oxidation state. In recent years, the isolation of low-valent main-group compounds has attracted increasing attention of both experimental and theoretical chemists. This is not only due to their fascinating electronic structures and exceptional reactivities, but also their use as valuable precursors for the synthesis of exotic yet important chemical species. This has led to a better understanding of the intricate balance of the donor-acceptor properties of the ligand(s) used to stabilize elements in a formally zero-oxidation state. Owing to the unusual oxidation state of the central element, many compounds containing formally zero-valent elements can efficiently activate otherwise inert small molecules. This review describes the synthesis, characterization, and reactivity of reported mono and diatomic formal zero-oxidation state main-group compounds. This review also emphasizes the comparative description of systems where different ligands are used to stabilize an element in its formal zero-oxidation state.
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Affiliation(s)
- Ravi Yadav
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110 016, India. .,Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, 69120 Heidelberg, Germany
| | - Soumen Sinhababu
- Department of Chemistry, University of Illinois at Chicago, 845 W. Taylor St., Chicago, Illinois 60607, USA.
| | - Ritu Yadav
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110 016, India.
| | - Subrata Kundu
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110 016, India.
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19
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García-Garrido SE, Presa Soto A, García-Álvarez J. Iminophosphoranes (R3P NR′): From terminal to multidentate ligands in organometallic chemistry. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2022. [DOI: 10.1016/bs.adomc.2022.01.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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20
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Feichtner KS, Scharf LT, Scherpf T, Mallick B, Boysen N, Gessner VH. Tuning Ruthenium Carbene Complexes for Selective P-H Activation through Metal-Ligand Cooperation. Chemistry 2021; 27:17351-17360. [PMID: 34705314 PMCID: PMC9299219 DOI: 10.1002/chem.202103151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Indexed: 11/14/2022]
Abstract
The use of iminophosphoryl‐tethered ruthenium carbene complexes to activate secondary phosphine P−H bonds is reported. Complexes of type [(p‐cymene)‐RuC(SO2Ph)(PPh2NR)] (with R = SiMe3 or 4‐C6H4−NO2) were found to exhibit different reactivities depending on the electronics of the applied phosphine and the substituent at the iminophosphoryl moiety. Hence, the electron‐rich silyl‐substituted complex undergoes cyclometallation or shift of the imine moiety after cooperative activation of the P−H bond across the M=C linkage, depending on the electronics of the applied phosphine. Deuteration experiments and computational studies proved that cyclometallation is initiated by the activation process at the M=C bond and triggered by the high electron density at the metal in the phosphido intermediates. Consistently, replacement of the trimethylsilyl (TMS) group by the electron‐withdrawing 4‐nitrophenyl substituent allowed the selective cooperative P−H activation to form stable activation products.
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Affiliation(s)
- Kai-Stephan Feichtner
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Lennart T Scharf
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Thorsten Scherpf
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Bert Mallick
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Nils Boysen
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Viktoria H Gessner
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstrasse 150, 44780, Bochum, Germany
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21
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Feuerstein W, Varava P, Fadaei-Tirani F, Scopelliti R, Severin K. Synthesis, structural characterization, and coordination chemistry of imidazole-based alkylidene ketenes. Chem Commun (Camb) 2021; 57:11509-11512. [PMID: 34652353 DOI: 10.1039/d1cc05161j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Alkylidene ketenes typically display high intrinsic reactivity, impeding isolation on a preparative scale. Herein, we report the synthesis of alkylidene ketenes by reaction of imidazole-based diazoolefins with carbon monoxide. The good thermal stability of these heterocumulenes allows for characterization by single crystal X-ray diffraction. N-Heterocyclic alkylidene ketenes can be used as C-donor ligands for transition and main group metals, as evidenced by the isolation of complexes with AuCl, RhCl(CO)2, PdCl(C3H5) and GaCl3.
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Affiliation(s)
- Wolfram Feuerstein
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
| | - Paul Varava
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
| | - Farzaneh Fadaei-Tirani
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
| | - Rosario Scopelliti
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
| | - Kay Severin
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
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22
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Varava P, Dong Z, Scopelliti R, Fadaei-Tirani F, Severin K. Isolation and characterization of diazoolefins. Nat Chem 2021; 13:1055-1060. [PMID: 34621076 DOI: 10.1038/s41557-021-00790-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 08/17/2021] [Indexed: 11/09/2022]
Abstract
Diazoolefins tend to be highly reactive compounds that rapidly lose dinitrogen. So far, most experimental evidence for diazoolefins is indirect, via trapping experiments. Here we show that diazoolefins are observed to form in reactions of N-heterocyclic olefins with nitrous oxide. The products benefit from resonance stabilization, which enables isolation on a preparative scale, and comprehensive characterization, which includes crystallographic analyses. N-heterocyclic diazoolefins show a strong ylidic character, with a high charge density at the carbon atom next to the diazo group. Despite the presence of terminal N2 groups, N-heterocyclic diazoolefins display a good thermal stability, which surpasses that observed for most diazoalkanes. N-heterocyclic diazoolefins can bind transition and main group metal complexes without the liberation of dinitrogen, and spectroscopic data show that they are strong electron donors. They can also undergo reactions that involve the N2 group, as evidenced by cycloaddition reactions.
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Affiliation(s)
- Paul Varava
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Zhaowen Dong
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Rosario Scopelliti
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Farzaneh Fadaei-Tirani
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Kay Severin
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
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23
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Chan YC, Bai Y, Chen WC, Chen HY, Li CY, Wu YY, Tseng MC, Yap GPA, Zhao L, Chen HY, Ong TG. Synergistic Catalysis by Brønsted Acid/Carbodicarbene Mimicking Frustrated Lewis Pair-Like Reactivity. Angew Chem Int Ed Engl 2021; 60:19949-19956. [PMID: 34128303 DOI: 10.1002/anie.202107127] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Indexed: 01/06/2023]
Abstract
Carbodicarbene (CDC), unique carbenic entities bearing two lone pairs of electrons are well-known for their strong Lewis basicity. We demonstrate herein, upon introducing a weak Brønsted acid benzyl alcohol (BnOH) as a co-modulator, CDC is remolded into a Frustrated Lewis Pair (FLP)-like reactivity. DFT calculation and experimental evidence show BnOH loosely interacting with the binding pocket of CDC via H-bonding and π-π stacking. Four distinct reactions in nature were deployed to demonstrate the viability of proof-of-concept as synergistic FLP/Modulator (CDC/BnOH), demonstrating enhanced catalytic reactivity in cyclotrimerization of isocyanate, polymerization process for L-lactide (LA), methyl methacrylate (MMA) and dehydrosilylation of alcohols. Importantly, the catalytic reactivity of carbodicarbene is uniquely distinct from conventional NHC which relies on only single chemical feature of nucleophilicity. This finding also provides a new spin in diversifying FLP reactivity with co-modulator or co-catalyst.
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Affiliation(s)
- Yi-Chen Chan
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan, R.O.C.,Department of Applied Chemistry, National Yang Ming Chiao Tung University, Hsinchu, Taiwan, R.O.C.,Taiwan International Graduate Program (TIGP), Sustainable Chemical Science and Technology (SCST), Academia Sinica, Taipei, Taiwan, R.O.C
| | - Yuna Bai
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, China
| | - Wen-Ching Chen
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan, R.O.C
| | - Hsing-Yin Chen
- Department of Medicinal and Applied Chemistry, Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan, R.O.C
| | - Chen-Yu Li
- Department of Medicinal and Applied Chemistry, Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan, R.O.C
| | - Ying-Yann Wu
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan, R.O.C
| | - Mei-Chun Tseng
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan, R.O.C
| | - Glenn P A Yap
- The Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, USA
| | - Lili Zhao
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, China
| | - Hsuan-Ying Chen
- Department of Medicinal and Applied Chemistry, Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan, R.O.C.,Department of Medicinal Research, Kaohsiung Medical University Hospital, Kaohsiung, 80708, Taiwan, R.O.C
| | - Tiow-Gan Ong
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan, R.O.C.,Department of Chemistry, National (Taiwan) University, Taipei, Taiwan, R.O.C
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24
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Chan Y, Bai Y, Chen W, Chen H, Li C, Wu Y, Tseng M, Yap GPA, Zhao L, Chen H, Ong T. Synergistic Catalysis by Brønsted Acid/Carbodicarbene Mimicking Frustrated Lewis Pair‐Like Reactivity. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202107127] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Yi‐Chen Chan
- Institute of Chemistry Academia Sinica Taipei Taiwan, R.O.C
- Department of Applied Chemistry National Yang Ming Chiao Tung University Hsinchu Taiwan, R.O.C
- Taiwan International Graduate Program (TIGP) Sustainable Chemical Science and Technology (SCST) Academia Sinica Taipei Taiwan, R.O.C
| | - Yuna Bai
- Institute of Advanced Synthesis School of Chemistry and Molecular Engineering Nanjing Tech University Nanjing China
| | - Wen‐Ching Chen
- Institute of Chemistry Academia Sinica Taipei Taiwan, R.O.C
| | - Hsing‐Yin Chen
- Department of Medicinal and Applied Chemistry Drug Development and Value Creation Research Center Kaohsiung Medical University Kaohsiung 80708 Taiwan, R.O.C
| | - Chen‐Yu Li
- Department of Medicinal and Applied Chemistry Drug Development and Value Creation Research Center Kaohsiung Medical University Kaohsiung 80708 Taiwan, R.O.C
| | - Ying‐Yann Wu
- Institute of Chemistry Academia Sinica Taipei Taiwan, R.O.C
| | - Mei‐Chun Tseng
- Institute of Chemistry Academia Sinica Taipei Taiwan, R.O.C
| | - Glenn P. A. Yap
- The Department of Chemistry and Biochemistry University of Delaware Newark DE USA
| | - Lili Zhao
- Institute of Advanced Synthesis School of Chemistry and Molecular Engineering Nanjing Tech University Nanjing China
| | - Hsuan‐Ying Chen
- Department of Medicinal and Applied Chemistry Drug Development and Value Creation Research Center Kaohsiung Medical University Kaohsiung 80708 Taiwan, R.O.C
- Department of Medicinal Research Kaohsiung Medical University Hospital Kaohsiung, 80708 Taiwan, R.O.C
| | - Tiow‐Gan Ong
- Institute of Chemistry Academia Sinica Taipei Taiwan, R.O.C
- Department of Chemistry National (Taiwan) University Taipei Taiwan, R.O.C
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25
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Singh T, Sahoo SC, Bharatam PV. Compound with possible N → N coordination bond: Synthesis, crystal structure and electronic structure analysis. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.153246] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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26
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Fan J, Yang MC, Hooper TJN, Su MD, So CW. Diboron-Carbene Complexes Derived from a Geminal Dianion. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jun Fan
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371
| | - Ming-Chung Yang
- Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan
| | - Thomas J. N. Hooper
- High Field NMR Facility, Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371
| | - Ming-Der Su
- Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan
- Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Cheuk-Wai So
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371
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27
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Munz D, Meyer K. Charge frustration in ligand design and functional group transfer. Nat Rev Chem 2021; 5:422-439. [PMID: 37118028 DOI: 10.1038/s41570-021-00276-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/25/2021] [Indexed: 02/08/2023]
Abstract
Molecules with different resonance structures of similar importance, such as heterocumulenes and mesoionics, are prominent in many applications of chemistry, including 'click chemistry', photochemistry, switching and sensing. In coordination chemistry, similar chameleonic/schizophrenic entities are referred to as ambidentate/ambiphilic or cooperative ligands. Examples of these had remained, for a long time, limited to a handful of archetypal compounds that were mere curiosities. In this Review, we describe ambiphilicity - or, rather, 'charge frustration' - as a general guiding principle for ligand design and functional group transfer. We first give a historical account of organic zwitterions and discuss their electronic structures and applications. Our discussion then focuses on zwitterionic ligands and their metal complexes, such as those of ylidic and redox-active ligands. Finally, we present new approaches to single-atom transfer using cumulated small molecules and outline emerging areas, such as bond activation and stable donor-acceptor ligand systems for reversible 1e- chemistry or switching.
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Liu J, Singh K, Dutta S, Feng Z, Koley D, Tan G, Wang X. Yttrium germole dianion complexes with Y-Ge bonds. Dalton Trans 2021; 50:5552-5556. [PMID: 33908995 DOI: 10.1039/d1dt00798j] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reactions of dipotassium 3,4-dimethyl-2,5-bis(trimethylsilyl)-germole dianion K2[1] with YCl3 and Cp*YCl2 (Cp* = cyclopentadienyl) in THF at room temperature afforded the dianion salt [(K-cryptand-222)2][1-YCl3] (K2[2]) and the dimeric complex [1-Y-Cp*]2 (3), respectively. While the polymeric complex {[(1)2-Y-K(toluene)]2}n (4) was obtained from the reaction of K2[1] and half molar equivalent of YCl3(THF)3.5 in toluene at 80 °C. The germole dianions in complexes 3 and 4 feature η5/η1 coordination interactions with the yttrium atoms. They represent the first examples of rare earth (RE) complexes containing RE-Ge bonds other than the RE-GeR3 structural type.
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Affiliation(s)
- Jingjing Liu
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China.
| | - Kalyan Singh
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur 741246, India.
| | - Sayan Dutta
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur 741246, India.
| | - Zhongtao Feng
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210023, China
| | - Debasis Koley
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur 741246, India.
| | - Gengwen Tan
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China.
| | - Xinping Wang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210023, China
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29
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Complexes of Dichlorogermylene with Phosphine/Sulfoxide-Supported Carbone as Ligand. Molecules 2021; 26:molecules26072005. [PMID: 33916075 PMCID: PMC8037485 DOI: 10.3390/molecules26072005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 03/25/2021] [Accepted: 03/29/2021] [Indexed: 11/17/2022] Open
Abstract
Due to their remarkable electronic features, recent years have witnessed the emergence of carbones L2C, which consist in two donating L ligands coordinating a central carbon atom bearing two lone pairs. In this context, the phosphine/sulfoxide-supported carbone 4 exhibits a strong nucleophilic character, and here, we describe its ability to coordinate dichlorogermylene. Two original stable coordination complexes were obtained and fully characterized in solution and in the solid state by NMR spectroscopy and X-ray diffraction analysis, respectively. At 60 °C, in the presence of 4, the Ge(II)-complex 5 undergoes a slow isomerization that transforms the bis-ylide ligand into an yldiide.
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30
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Chia CC, Teo YC, Cham N, Ho SYF, Ng ZH, Toh HM, Mézailles N, So CW. Aluminum-Hydride-Catalyzed Hydroboration of Carbon Dioxide. Inorg Chem 2021; 60:4569-4577. [PMID: 33733776 DOI: 10.1021/acs.inorgchem.0c03507] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
This study describes the first use of a bis(phosphoranyl)methanido aluminum hydride, [ClC(PPh2NMes)2AlH2] (2, Mes = Me3C6H2), for the catalytic hydroboration of CO2. Complex 2 was synthesized by the reaction of a lithium carbenoid [Li(Cl)C(PPh2NMes)2] with 2 equiv of AlH3·NEtMe2 in toluene at -78 °C. 2 (10 mol %) was able to catalyze the reduction of CO2 with HBpin in C6D6 at 110 °C for 2 days to afford a mixture of methoxyborane [MeOBpin] (3a; yield: 78%, TOF: 0.16 h-1) and bis(boryl)oxide [pinBOBpin] (3b). When more potent [BH3·SMe2] was used instead of HBpin, the catalytic reaction was extremely pure, resulting in the formation of trimethyl borate [B(OMe)3] (3e) [catalytic loading: 1 mol % (10 mol %); reaction time: 60 min (5 min); yield: 97.6% (>99%); TOF: 292.8 h-1 (356.4 h-1)] and B2O3 (3f). Mechanistic studies show that the Al-H bond in complex 2 activated CO2 to form [ClC(PPh2NMes)2Al(H){OC(O)H}] (4), which was subsequently reacted with BH3·SMe2 to form 3e and 3f, along with the regeneration of complex 2. Complex 2 also shows good catalytic activity toward the hydroboration of carbonyl, nitrile, and alkyne derivatives.
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Affiliation(s)
- Cher-Chiek Chia
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371
| | - Yeow-Chuan Teo
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371
| | - Ning Cham
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371
| | - Samuel Ying-Fu Ho
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371.,Laboratoire Hétérochimie Fondamentale et Appliquée, CNRS, Université Paul Sabatier, 31062 Toulouse, France
| | - Zhe-Hua Ng
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371
| | - Hui-Min Toh
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371
| | - Nicolas Mézailles
- Laboratoire Hétérochimie Fondamentale et Appliquée, CNRS, Université Paul Sabatier, 31062 Toulouse, France
| | - Cheuk-Wai So
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371
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31
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Xu W, Maser L, Alig L, Langer R. Rhodium carbonyl complexes featuring carbodiphosphorane-based pincer ligands. Polyhedron 2021. [DOI: 10.1016/j.poly.2020.115018] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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32
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Maser L, Korziniowski P, Langer R. Flexible coordination of carbodiphosphorane-based pincer ligands in chromium(0) carbonyl complexes. CAN J CHEM 2021. [DOI: 10.1139/cjc-2020-0351] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A series of chromium(0) complexes was obtained by subsequent irradiation of [Cr(CO)6] in the presence of [(Ph2P-CH2-PPh2)2CH]+. Depending on the reaction conditions and the duration of irradiation, complexes with different coordination modes of the potentially tridentate ligand can be isolated. Shorter irradiation times lead to the coordination of the terminal PPh2 groups and the formation of [(κ2P,P′-{Ph2P-CH2-PPh2}CH)Cr(CO)4]+ (2), whereas after longer irradiation duration, the formation of fac- and mer-[(κ3P,C,P′-{Ph2P-CH2-PPh2}CH)Cr(CO)3]+ (3) can be observed. In the presence of base, the neutral complex [(κ3P,C,P′-{Ph2P-CH2-PPh2}C)Cr(CO)3] (4) can be isolated, enabling the analysis of the central CDP group’s net donor strength through the C–O stretching vibration. Finally, the utilization of reductants like potassium graphite lead to the loss of hydrogen and generation of an anionic chromium(0) complex (5). Using quantum chemical methods, the stability of possible isomers is explored.
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Affiliation(s)
- Leon Maser
- Institute of Chemistry, Natural Science Faculty II, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Str. 2, 06120 Halle (Saale), Germany
- Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Str. 4, 35032 Marburg, Germany
| | - Philipp Korziniowski
- Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Str. 4, 35032 Marburg, Germany
| | - Robert Langer
- Institute of Chemistry, Natural Science Faculty II, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Str. 2, 06120 Halle (Saale), Germany
- Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Str. 4, 35032 Marburg, Germany
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33
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Li Y, Maser L, Alig L, Ke Z, Langer R. From carbones to carbenes and ylides in the coordination sphere of iridium. Dalton Trans 2021; 50:954-959. [PMID: 33351021 DOI: 10.1039/d0dt03942j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The carbodiphosphorane-based iridium pincer complex (2) is demonstrated to rearrange in chlorinated organic solvents under cleavage of a P-C-bond to give a chelating phosphine ylide ligand. A detailed mechanistic investigation reveals that these types of donor groups are prone for P-C-bond cleavage in the coordination sphere of transition metal hydrido complexes. Finally, complex 2 is demonstrated to be an efficient hydrogen-borrowing catalyst.
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Affiliation(s)
- Yinwu Li
- School of Materials Science & Engineering, PCFM Lab, Sun Yat-sen University, Guangzhou 510275, China
| | - Leon Maser
- Institute of Chemistry, Faculty of Natural Sciences II, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Str. 2, D-06120 Halle (Saale), Germany. and Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Str., 35032 Marburg, Germany
| | - Lukas Alig
- Institute of Chemistry, Faculty of Natural Sciences II, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Str. 2, D-06120 Halle (Saale), Germany.
| | - Zhuofeng Ke
- School of Materials Science & Engineering, PCFM Lab, Sun Yat-sen University, Guangzhou 510275, China
| | - Robert Langer
- Institute of Chemistry, Faculty of Natural Sciences II, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Str. 2, D-06120 Halle (Saale), Germany. and Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Str., 35032 Marburg, Germany
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34
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Au-Yeung KC, Xiao D, Shih WC, Yang HW, Wen YS, Yap GPA, Chen WC, Zhao L, Ong TG. Carbodicarbene: geminal-Bimetallic Coordination in Selective Manner. Chemistry 2020; 26:17350-17355. [PMID: 32537790 DOI: 10.1002/chem.202002795] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 06/12/2020] [Indexed: 01/07/2023]
Abstract
The reaction of Pd(OAc)2 with free carbodicarbene (CDC) generates a Pd acetate trinuclear complex 1 via intramolecular C(sp3 )-H bond activation at one of the CDC methyl side arms. The solid structure of 1 reveals the capability of CDC to facilitate a double dative bond with two palladium centers in geminal fashion. This is attributed to the chelating mode of CDC, which can frustrate π-conjugation within the CDC framework. Such effect maybe also amplified by ligand-ligand interaction. The formation of other gem-bimetallic Pd-Pd, Pd-Au, and Ni-Au provides further structural evidence for this proof-of-concept in selective installation. Structural analysis is supported by computational calculations based on state-of-the-art energy decomposition analysis (EDA) in conjunction with natural orbitals for chemical valence (NOCV) method.
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Affiliation(s)
| | - Dengmengfei Xiao
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, P.R. China
| | - Wei-Chih Shih
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan
| | - Hsiu-Wen Yang
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan
| | - Yuh-Sheng Wen
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan
| | - Glenn P A Yap
- Department of Chemistry & Biochemistry, University of Delaware, USA
| | | | - Lili Zhao
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, P.R. China
| | - Tiow-Gan Ong
- Institute of Chemistry, Academia Sinica, Taipei, Taiwan.,Department of Applied Chemistry, National Chiao Tung University, Taipei, Taiwan.,Department of Chemistry, National Taiwan University, Taipei, Taiwan
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35
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Gupta R, Rezabal E, Hasrack G, Frison G. Comparison of Chemical and Interpretative Methods: the Carbon-Boron π-Bond as a Test Case*. Chemistry 2020; 26:17230-17241. [PMID: 32780465 DOI: 10.1002/chem.202001945] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 08/05/2020] [Indexed: 12/16/2022]
Abstract
Quantum chemical calculations and NBO, ETS-NOCV, QTAIM and ELF interpretative approaches have been carried out on C-donor ligand-stabilized dihydrido borenium cations. Numerous descriptors of the C-B π-bond strength obtained from orbital localization, energy partitioning or topological methods as well as from structural and chemical parameters have been calculated for 39 C-donor ligands including N-heterocyclic carbenes and carbones. Comparison of the results allows the identification of relative and absolute descriptors of the π interaction. For both families of descriptors excellent correlations are obtained. This enables the establishment of a π-donation capability scale and shows that the interpretative methods, despite their conceptual differences, describe the same chemical properties. These results also reveal noticeable shortcomings in these popular methods, and some precautions that need to be taken to interpret their results adequately.
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Affiliation(s)
- Radhika Gupta
- LCM, CNRS, École polytechnique, Institut Polytechnique de Paris, 91128, Palaiseau, France
| | - Elixabete Rezabal
- LCM, CNRS, École polytechnique, Institut Polytechnique de Paris, 91128, Palaiseau, France.,Faculty of Chemistry, Donostia International Physics Center (DIPC), University of the Basque Country UPV/EHU, 20018, Donostia, Spain
| | - Golshid Hasrack
- LCM, CNRS, École polytechnique, Institut Polytechnique de Paris, 91128, Palaiseau, France
| | - Gilles Frison
- LCM, CNRS, École polytechnique, Institut Polytechnique de Paris, 91128, Palaiseau, France
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36
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Kroll A, Steinert H, Jörges M, Steinke T, Mallick B, Gessner VH. Cationic Phosphorus Compounds Based on a Bis(1-piperidinyl)-Substituted Carbodiphosphorane: Syntheses, Structures, and C sp3–H Activation. Organometallics 2020; 39:4312-4319. [PMID: 33551536 PMCID: PMC7861138 DOI: 10.1021/acs.organomet.0c00412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Indexed: 11/29/2022]
Abstract
![]()
The use of the bis(1-piperidinyl)-substituted carbodiphosphorane
(Ph2(Pip)P)2C (1) as an NCN ligand for the
stabilization of phosphorus cations was studied. A simple ligand for halide exchange
allowed the synthesis and isolation of a series of phosphorus monocations of the type
[1-PR2]+ (with R = Cl, Br, I, CyCl, Ph). These
cations exhibit characteristic NMR and structural properties which nicely correlate with
the charge at the central phosphorus atom and the interaction between the ligand and the
PR2 moiety. Halide abstraction from the monocations does not result in
isolable dicationic compounds but in an unexpected intramolecular
Csp3–H activation in the piperidinyl group. DFT studies
show that the selective activation of the CH2 group next to the nitrogen atom
instead of a CH group at the phenyl substituents proceeds via an iminium intermediate
formed by hydride transfer from the carbon atom to the cationic phosphorus center. This
observation clearly demonstrates the pronounced π acidity of the dicationic
phosphorus species in comparison to compounds with a further π-donor
substituent.
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Affiliation(s)
- Alexander Kroll
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Henning Steinert
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Mike Jörges
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Tim Steinke
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Bert Mallick
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Viktoria H. Gessner
- Chair of Inorganic Chemistry II, Faculty of Chemistry and Biochemistry, Ruhr-University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
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37
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Zhang Y, Wu B, Zhong M, Zhang WX, Xi Z. Cyclic Bis-alkylidene Complexes of Titanium and Zirconium: Synthesis, Characterization, and Reaction. Chemistry 2020; 26:16472-16479. [PMID: 32875626 DOI: 10.1002/chem.202003240] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 08/29/2020] [Indexed: 11/06/2022]
Abstract
Transition-metal alkylidenes have exhibited wide applications in organometallic chemistry and synthetic organic chemistry, however, cyclic Schrock-carbene-like bis-alkylidenes of group 4 metals with a four-electron donor from an alkylidene have not been reported. Herein, the synthesis and characterization of five-membered cyclic bis-alkylidenes of titanium (4 a,b) and zirconium (5 a,b) are reported, as the first well-defined group 4 metallacyclopentatrienes, by two-electron reduction of their corresponding titana- and zirconacyclopentadienes. DFT analyses of 4 a show a four-electron donor (σ-donation and π-donation) from an alkylidene carbon to the metal center. The reaction of 4 a with N,N'-diisopropylcarbodiimide (DIC) leads to the [2+2]-cycloaddition product 6. Compound 4 a reacted with CO, affording the oxycyclopentadienyl titanium complex 7. These reactivities demonstrate the multiple metal-carbon bond character. The reactions of 4 a or 5 a with cyclooctatetraene (COT) or azobenzene afforded sandwich titanium complex 8 or diphenylhydrazine-coordinated zirconacyclopentadiene 9, respectively, which exhibit two-electron reductive ability.
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Affiliation(s)
- Yongliang Zhang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, P.R. China
| | - Botao Wu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, P.R. China
| | - Mingdong Zhong
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, P.R. China
| | - Wen-Xiong Zhang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, P.R. China
| | - Zhenfeng Xi
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, 100871, P.R. China.,State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Shanghai, 200032, P.R. China
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38
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Zhao L, Chai C, Petz W, Frenking G. Carbones and Carbon Atom as Ligands in Transition Metal Complexes. Molecules 2020; 25:molecules25214943. [PMID: 33114580 PMCID: PMC7663554 DOI: 10.3390/molecules25214943] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 10/08/2020] [Accepted: 10/15/2020] [Indexed: 01/22/2023] Open
Abstract
This review summarizes experimental and theoretical studies of transition metal complexes with two types of novel metal-carbon bonds. One type features complexes with carbones CL2 as ligands, where the carbon(0) atom has two electron lone pairs which engage in double (σ and π) donation to the metal atom [M]⇇CL2. The second part of this review reports complexes which have a neutral carbon atom C as ligand. Carbido complexes with naked carbon atoms may be considered as endpoint of the series [M]-CR3 → [M]-CR2 → [M]-CR → [M]-C. This review includes some work on uranium and cerium complexes, but it does not present a complete coverage of actinide and lanthanide complexes with carbone or carbide ligands.
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Affiliation(s)
- Lili Zhao
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China; (L.Z.); (C.C.)
| | - Chaoqun Chai
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China; (L.Z.); (C.C.)
| | - Wolfgang Petz
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, D-35043 Marburg, Germany
- Correspondence: (W.P.); (G.F.)
| | - Gernot Frenking
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China; (L.Z.); (C.C.)
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, D-35043 Marburg, Germany
- Correspondence: (W.P.); (G.F.)
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39
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Normand AT, Sosa Carrizo ED, Magnoux C, Lobato E, Cattey H, Richard P, Brandès S, Devillers CH, Romieu A, Le Gendre P, Fleurat-Lessard P. Reappraising Schmidpeter's bis(iminophosphoranyl)phosphides: coordination to transition metals and bonding analysis. Chem Sci 2020; 12:253-269. [PMID: 34163594 PMCID: PMC8178813 DOI: 10.1039/d0sc04736h] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 10/25/2020] [Indexed: 11/21/2022] Open
Abstract
The synthesis and characterization of a range of bis(iminophosphoranyl)phosphide (BIPP) group 4 and coinage metals complexes is reported. BIPP ligands bind group 4 metals in a pseudo fac-fashion, and the central phosphorus atom enables the formation of d0-d10 heterobimetallic complexes. Various DFT computational tools (including AIM, ELF and NCI) show that the phosphorus-metal interaction is either electrostatic (Ti) or dative (Au, Cu). A bridged homobimetallic Cu-Cu complex was also prepared and its spectroscopic properties were investigated. The theoretical analysis of the P-P bond in BIPP complexes reveals that (i) BIPP are closely related to ambiphilic triphosphenium (TP) cations; (ii) the P-P bonds are normal covalent (i.e. not dative) in both BIPP and TP.
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Affiliation(s)
- Adrien T Normand
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB), UMR 6302, CNRS, Université de Bourgogne 9, Avenue Alain Savary 21000 Dijon France
| | - E Daiann Sosa Carrizo
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB), UMR 6302, CNRS, Université de Bourgogne 9, Avenue Alain Savary 21000 Dijon France
| | - Corentin Magnoux
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB), UMR 6302, CNRS, Université de Bourgogne 9, Avenue Alain Savary 21000 Dijon France
| | - Esteban Lobato
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB), UMR 6302, CNRS, Université de Bourgogne 9, Avenue Alain Savary 21000 Dijon France
| | - Hélène Cattey
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB), UMR 6302, CNRS, Université de Bourgogne 9, Avenue Alain Savary 21000 Dijon France
| | - Philippe Richard
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB), UMR 6302, CNRS, Université de Bourgogne 9, Avenue Alain Savary 21000 Dijon France
| | - Stéphane Brandès
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB), UMR 6302, CNRS, Université de Bourgogne 9, Avenue Alain Savary 21000 Dijon France
| | - Charles H Devillers
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB), UMR 6302, CNRS, Université de Bourgogne 9, Avenue Alain Savary 21000 Dijon France
| | - Anthony Romieu
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB), UMR 6302, CNRS, Université de Bourgogne 9, Avenue Alain Savary 21000 Dijon France
| | - Pierre Le Gendre
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB), UMR 6302, CNRS, Université de Bourgogne 9, Avenue Alain Savary 21000 Dijon France
| | - Paul Fleurat-Lessard
- Institut de Chimie Moléculaire de l'Université de Bourgogne (ICMUB), UMR 6302, CNRS, Université de Bourgogne 9, Avenue Alain Savary 21000 Dijon France
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Vollhardt J, Lindner HJ, Gais HJ. Isolation and structure determination of a tetrameric sulfonyl dilithio methandiide in solution based on crystal structure analysis and 6Li/ 13C NMR spectroscopic data. Beilstein J Org Chem 2020; 16:2057-2063. [PMID: 32874352 PMCID: PMC7445413 DOI: 10.3762/bjoc.16.172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 08/03/2020] [Indexed: 12/01/2022] Open
Abstract
Dilithio sulfonyl methandiides are a synthetically and structurally highly interesting group of functionalized geminal dianions. Although very desirable, knowledge of the structure of dilithio methandiides in solution was lacking up to now. Herein, we describe the isolation and determination of the structure of tetrameric dilithio (trimethylsilyl)(phenylsulfonyl) methandiide in solution and in the crystal. The elucidation of the structure of the tetramer is based on crystal structure analysis and 13C/6Li NMR spectroscopic data. A characteristic feature of the structure of the tetramer is the C2 symmetric C–Li chain, composed of four doubly Li-coordinated dianionic carbon and five Li atoms. Three Li atoms are devoid of a contact to a dianionic C atom. The tetramer, the dianionic C atoms of which undergo fast exchange, is in THF solution in fast equilibrium with a further aggregate, which is stable only at low temperatures.
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Affiliation(s)
- Jürgen Vollhardt
- DSM Nutritional Products, Wurmisweg 576, 4303 Kaiseraugst, Switzerland
| | - Hans Jörg Lindner
- Clemens-Schöpf Institute of Organic Chemistry, Technische Universität Darmstadt, Alarich-Weiss-Straße 4, 64287 Darmstadt, Germany
| | - Hans-Joachim Gais
- Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany
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41
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Böttger S, Gruber M, Münzer JE, Bernard GM, Kneusels NJH, Poggel C, Klein M, Hampel F, Neumüller B, Sundermeyer J, Michaelis VK, Tonner R, Tykwinski RR, Kuzu I. Solvent-Induced Bond-Bending Isomerism in Hexaphenyl Carbodiphosphorane: Decisive Dispersion Interactions in the Solid State. Inorg Chem 2020; 59:12054-12064. [DOI: 10.1021/acs.inorgchem.0c00994] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Silas Böttger
- Department of Chemistry, Philipps-University of Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | - Marco Gruber
- Interdisciplinary Center of Molecular Materials (ICMM), Department of Chemistry and Pharmacy, Friedrich-Alexander-University of Erlangen-Nuremberg (FAU), Nikolaus-Fiebiger-Straße 10, 91058 Erlangen, Germany
| | - Jörn Eike Münzer
- Department of Chemistry, Philipps-University of Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | - Guy M. Bernard
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Nis-Julian H. Kneusels
- Department of Chemistry, Philipps-University of Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | - Christina Poggel
- Department of Chemistry, Philipps-University of Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | - Marius Klein
- Department of Chemistry, Philipps-University of Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | - Frank Hampel
- Interdisciplinary Center of Molecular Materials (ICMM), Department of Chemistry and Pharmacy, Friedrich-Alexander-University of Erlangen-Nuremberg (FAU), Nikolaus-Fiebiger-Straße 10, 91058 Erlangen, Germany
| | - Bernhard Neumüller
- Department of Chemistry, Philipps-University of Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | - Jörg Sundermeyer
- Department of Chemistry, Philipps-University of Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | | | - Ralf Tonner
- Department of Chemistry, Philipps-University of Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | - Rik R. Tykwinski
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Istemi Kuzu
- Department of Chemistry, Philipps-University of Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
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Abstract
Enolates have proven to be one of the key building blocks available to the synthetic chemist. Here we summarize a novel strategy for their preparation, involving the addition of α-borylated nucleophiles to esters to yield boron enolates. The enolates prepared by the addition of lithiated geminal bis(boron) compounds to esters can be trapped with two equivalents of halogen and alkyl electrophiles to yield α,α-difunctionalized compounds.1 Introduction2 Ketone Difunctionalization3 Boron Enolates by Coupling4 Towards Sequential Trapping5 Summary and Outlook
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Kneusels NJH, Münzer JE, Flosdorf K, Jiang D, Neumüller B, Zhao L, Eichhöfer A, Frenking G, Kuzu I. Double donation in trigonal planar iron-carbodiphosphorane complexes - a concise study on their spectroscopic and electronic properties. Dalton Trans 2020; 49:2537-2546. [PMID: 32022052 DOI: 10.1039/c9dt04725e] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
We present the syntheses of trigonal planar coordinated Fe(ii) carbodiphosphorane (CDPR) complexes, starting from iron(ii)-bis(trimethylsilylamide) [Fe{N(SiMe3)2}2] and hexaphenyl-(CDPPh) and sym-dimethyltetraphenyl-carbodiphosphoranes (CDPMe), respectively. Both complexes [CDPPh-Fe{N(SiMe3)2}2] (1) and [CDPMe-Fe{N(SiMe3)2}2] (2) were examined in solution and in the solid state. 1 shows a dissociation equilibrium in solution which we monitored by variable temperature 1H-NMR spectroscopy. Magnetic measurements of 1 and 2 yielded a high spin configuration (S = 2) for both complexes. Quantum chemical calculations were performed to analyze the bonding situation in compound 1.
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Affiliation(s)
- Nis-Julian H Kneusels
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, D-35032 Marburg, Germany.
| | - Jörn E Münzer
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, D-35032 Marburg, Germany.
| | - Kimon Flosdorf
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, D-35032 Marburg, Germany.
| | - Dandan Jiang
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China.
| | - Bernhard Neumüller
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, D-35032 Marburg, Germany.
| | - Lili Zhao
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China.
| | - Andreas Eichhöfer
- Institut für Nanotechnologie, Karlsruher Institut für Technologie (KIT), Campus Nord, Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany.
| | - Gernot Frenking
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, D-35032 Marburg, Germany. and Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China.
| | - Istemi Kuzu
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, D-35032 Marburg, Germany.
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