1
|
Lynch JR, Kennedy AR, Barker J, Mulvey RE. Modification of a Common β-diketiminate NacNac Framework via Sequential Lithiation and Small Molecule Insertion. Chemistry 2023:e202303373. [PMID: 38032346 DOI: 10.1002/chem.202303373] [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: 10/13/2023] [Revised: 11/23/2023] [Accepted: 11/30/2023] [Indexed: 12/01/2023]
Abstract
A widely utilised class of ligands in synthesis and catalysis, β-diketiminate (BDI) or NacNac compounds were initially considered innocent in the sense that they remained intact in all their applications. That changed when the γ-C-H unit of their NCCCN backbone was found to engage in reactions with electrophiles. Here, we show that this special reactivity can be used advantageously to prepare tripodal modifications of the common NacNac ligand derived from 2,6-diisopropylphenyl-β-methyldiketimine [NacNacH (Me, Dipp)]. Lithiation to give NacNacLi, followed by reactions with isocyanates, isothiocyanates and a carbodiimide, have afforded a series of tripodal NacNac variants having N,N,N,O; N,N,N,S; or N,N,N,N potential dentation sites, many of which have been crystallographically characterised. Distinct ligating modes of these new ligands have been elucidated through the crystal structures of their lithiated derivatives.
Collapse
Affiliation(s)
- Jennifer R Lynch
- Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK
| | - Alan R Kennedy
- Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK
| | - Jim Barker
- Innospec Ltd., Oil Sites Road, Ellesmere Port, Cheshire, CH65 4EY, UK
| | - Robert E Mulvey
- Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK
| |
Collapse
|
2
|
Manankandayalage CP, Katakam N, Unruh DK, Aquino AJA, Krempner C. Intramolecular frustrated Lewis pair mediated approach to the CO bond activation and cleavage of carbon dioxide. Chem Commun (Camb) 2022; 58:9385-9388. [PMID: 35904557 DOI: 10.1039/d2cc03413a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A thermally stable FLP-CO2 adduct of pronounced nucleophilic properties that forms a range of Lewis acid-base adducts with strong Lewis acids is reported. Upon addition of Tf2O, it generates a cationic triflate, which undergoes C-O bond cleavage to give the formal FLP adduct of the elusive dication C2O32+.
Collapse
Affiliation(s)
- Chamila P Manankandayalage
- Department of Chemistry and Biochemistry, Texas Tech University, Memorial Dr & Boston, Lubbock, TX, 79409, USA.
| | - Nandakumar Katakam
- Department of Chemistry and Biochemistry, Texas Tech University, Memorial Dr & Boston, Lubbock, TX, 79409, USA.
| | - Daniel K Unruh
- Department of Chemistry and Biochemistry, Texas Tech University, Memorial Dr & Boston, Lubbock, TX, 79409, USA.
| | - Adelia J A Aquino
- Department of Mechanical Engineering, Texas Tech University, Lubbock, TX, 79409, USA
| | - Clemens Krempner
- Department of Chemistry and Biochemistry, Texas Tech University, Memorial Dr & Boston, Lubbock, TX, 79409, USA.
| |
Collapse
|
3
|
Zhao M, Xue T, He RR, Ma J, Zheng W. Ion-bearing stairs: alkali metal complexes of 1,2-diaza-4-phospholides. Dalton Trans 2022; 51:1634-1645. [PMID: 35007313 DOI: 10.1039/d1dt03601g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this work, eight alkali metal complexes with 1,2-diaza-4-phospholide ligands were prepared and characterized by X-ray single-crystal structural analysis and NMR spectroscopy. Their structures showed varied coordination motifs: (i) a dimeric 1,2-diaza-4-phospholide lithium complex with exo-bidentate bridging coordination (4) consists of two lithium atoms that are linked via two μ2-bridging, κN,κN'-coordinated ligands; (ii) the polymeric chain 1,2-diaza-4-phospholide potassium complex (5) showed an ion-bearing stair-shaped chain structure running through axis a, where the steps are η2 interactions, and there is a transition platform between every two stairs; (iii) the polymeric chain 1,2-diaza-4-phospholide potassium complex (6) also presented a polymeric chain structure in the solid state but displayed a head-to-tail arrangement of two 1,2-diaza-4-phospholides; (iv) in comparison to 6, the 1,2-diaza-4-phospholide sodium complex (7) displayed a tetrameric structure, in which the sodium ions are arranged in a distorted tetrahedral fashion and each of them occupies a vertex of the tetrahedron; (v) the polymeric chain 1,2-diaza-4-phospholide potassium complex (8) presented a solvent-free chain structure, in which potassium ions each is η5-bonded by two 1,2-diaza-4-phospholides and η2-coordinated by another, consisting of a stair-shaped chain structure running through axis a but without significant intermolecular contacts between the adjacent stairs in comparison to that of 5; (vi) the polymeric chain 1,2-diaza-4-phospholide sodium complex (9) presented a solvent-free chain structure, in which sodium ions each is η1(N),η2(N,N),η1(P)-bonded by three 1,2-diaza-4-phospholides, consisting of a chain structure running through axis a; and (vii) the treatment complex 8 with elemental sulphur or selenium in the presence of crown ether gave rare thiophosphonato potassium [η3(S,P,S)-3,5-tBu2dp-(μ-K)(S2)([18]crown-6)] (10) or a selenophosphonato potassium [η3(Se,P,Se)-3,5-tBu2dp-(μ-K)(Se2)([18]crown-6)] (11). Both of the complexes crystallized in the orthorhombic space group Pnma as pale-yellow (or red) crystals. The X-ray diffraction analysis revealed 10 or 11 as a terminal complex with the η1,η1-X,X-coordination mode (X = S and Se). The 1H DOSY NMR spectroscopy study of the species 8 in DMSO-d6 suggested that polymeric complexes (4-9) in the solid state should dissociate into the related monomers in the solutions when the donor solvents were used.
Collapse
Affiliation(s)
- Minggang Zhao
- Key Laboratory of Magnetic Molecules & Magnetic Information Materials Ministry of Education, The School of Chemical and Material Science, Shanxi Normal University, Taiyuan, Shanxi 030035, China.
| | - Tingting Xue
- Key Laboratory of Magnetic Molecules & Magnetic Information Materials Ministry of Education, The School of Chemical and Material Science, Shanxi Normal University, Taiyuan, Shanxi 030035, China.
| | - Ru-Ru He
- Key Laboratory of Magnetic Molecules & Magnetic Information Materials Ministry of Education, The School of Chemical and Material Science, Shanxi Normal University, Taiyuan, Shanxi 030035, China.
| | - Jianping Ma
- College of Chemistry, Chemical Engineering and Materials Science, Shandong Normal University, Jinan, Shandong 250014, China
| | - Wenjun Zheng
- Key Laboratory of Magnetic Molecules & Magnetic Information Materials Ministry of Education, The School of Chemical and Material Science, Shanxi Normal University, Taiyuan, Shanxi 030035, China. .,Wenbo Chemical Co., Ltd, Guonian Road 65, Shanghai, 200433, China
| |
Collapse
|
4
|
Gauld RM, McLellan R, Kennedy AR, Carson FJ, Barker J, Reid J, O'Hara CT, Mulvey RE. Structural Studies of Donor‐Free and Donor‐Solvated Sodium Carboxylates. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Richard M. Gauld
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde G1 1XL Glasgow UK
- Current address: Fakultät für Chemie und Biochemie Ruhr-Universität Bochum Universitätsstrasse 150 44801 Bochum Germany
| | - Ross McLellan
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde G1 1XL Glasgow UK
| | - Alan R. Kennedy
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde G1 1XL Glasgow UK
| | - Freya J. Carson
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde G1 1XL Glasgow UK
| | - Jim Barker
- Innospec Ltd, Innospec Manufacturing Park Oil Sites Road CH65 4EY Ellesmere Port Cheshire UK
| | - Jacqueline Reid
- Innospec Ltd, Innospec Manufacturing Park Oil Sites Road CH65 4EY Ellesmere Port Cheshire UK
| | - Charles T. O'Hara
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde G1 1XL Glasgow UK
| | - Robert E. Mulvey
- WestCHEM Department of Pure and Applied Chemistry University of Strathclyde G1 1XL Glasgow UK
| |
Collapse
|
5
|
Bayer U, Jenner A, Riedmaier J, Maichle-Mössmer C, Anwander R. Effect of Substituents of Cerium Pyrazolates and Pyrrolates on Carbon Dioxide Activation. Molecules 2021; 26:molecules26071957. [PMID: 33807172 PMCID: PMC8037029 DOI: 10.3390/molecules26071957] [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: 03/12/2021] [Revised: 03/22/2021] [Accepted: 03/24/2021] [Indexed: 02/05/2023] Open
Abstract
Homoleptic ceric pyrazolates (pz) Ce(RR’pz)4 (R = R’ = tBu; R = R’ = Ph; R = tBu, R’ = Me) were synthesized by the protonolysis reaction of Ce[N(SiHMe2)2]4 with the corresponding pyrazole derivative. The resulting complexes were investigated in their reactivity toward CO2, revealing a significant influence of the bulkiness of the substituents on the pyrazolato ligands. The efficiency of the CO2 insertion was found to increase in the order of tBu2pz < Ph2pz < tBuMepz < Me2pz. For comparison, the pyrrole-based ate complexes [Ce2(pyr)6(µ-pyr)2(thf)2][Li(thf)4]2 (pyr = pyrrolato) and [Ce(cbz)4(thf)2][Li(thf)4] (cbz = carbazolato) were obtained via protonolysis of the cerous ate complex Ce[N(SiHMe2)2]4Li(thf) with pyrrole and carbazole, respectively. Treatment of the pyrrolate/carbazolate complexes with CO2 seemed promising, but any reversibility could not be observed.
Collapse
|
6
|
Bresciani G, Biancalana L, Pampaloni G, Marchetti F. Recent Advances in the Chemistry of Metal Carbamates. Molecules 2020; 25:E3603. [PMID: 32784784 PMCID: PMC7465543 DOI: 10.3390/molecules25163603] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 07/31/2020] [Accepted: 08/03/2020] [Indexed: 12/12/2022] Open
Abstract
Following a related review dating back to 2003, the present review discusses in detail the various synthetic, structural and reactivity aspects of metal species containing one or more carbamato ligands, representing a large family of compounds across all the periodic table. A preliminary overview is provided on the reactivity of carbon dioxide with amines, and emphasis is given to recent findings concerning applications in various fields.
Collapse
Affiliation(s)
| | | | - Guido Pampaloni
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via G. Moruzzi 13, I-56124 Pisa, Italy; (G.B.); (L.B.)
| | - Fabio Marchetti
- Department of Chemistry and Industrial Chemistry, University of Pisa, Via G. Moruzzi 13, I-56124 Pisa, Italy; (G.B.); (L.B.)
| |
Collapse
|
7
|
Gauld RM, McLellan R, Kennedy AR, Barker J, Reid J, Mulvey RE. Backbone Reactivity of Lithium β-Diketiminate (NacNac) Complexes with CO 2 , tBuNCO and iPrNCO. Chemistry 2019; 25:14728-14734. [PMID: 31574177 DOI: 10.1002/chem.201904013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 09/27/2019] [Indexed: 01/07/2023]
Abstract
Though alkali metal NacNac (β-diketiminate) complexes have been utilised in synthesis as NacNac-transfer agents, studies of them in their own right with small molecules are exceptionally rare. Here, the lithium compound of the common 2,6-diisopropylphenyl-β-methyldiketiminate [NacNac(Dipp, Me)] ligand is investigated with carbon dioxide and isocyanates. In all four cases reaction occurs at the backbone γ-C atom of the NacNac ligand, which redistributes electronically into a diimine. Insertion of CO2 gives an eight-atom carboxylate (Li2 O4 C2 ) ring at the γ-C site in a dimer. Insertion of tBuNCO gives a secondary amide at the γ-C site in a monomer with TMEDA chelating lithium. Double insertion of tBuNCO and (adventitious) oxygen gives a dimer with a (LiO)2 central core involving the latter source. Insertion of less bulky (iPrNCO) gives a dimer with dimerisation through the C=O bonds of the emergent secondary amide function.
Collapse
Affiliation(s)
- Richard M Gauld
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK
| | - Ross McLellan
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK
| | - Alan R Kennedy
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK
| | - Jim Barker
- Innospec Ltd, Innospec Manufacturing Park, Oil Sites Road, Ellesmere Port, Cheshire, CH65 4EY, UK
| | - Jacqueline Reid
- Innospec Ltd, Innospec Manufacturing Park, Oil Sites Road, Ellesmere Port, Cheshire, CH65 4EY, UK
| | - Robert E Mulvey
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK
| |
Collapse
|