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Zheng X, Huang F, Li X, Zhuo K, Chen D, Luo M, Xia H. Isomerization reactions of metal vinylidene units. Chem Sci 2024; 15:8443-8450. [PMID: 38846407 PMCID: PMC11151869 DOI: 10.1039/d4sc01993h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Accepted: 04/29/2024] [Indexed: 06/09/2024] Open
Abstract
Isomerization reactions of unsaturated molecules offer an efficient strategy in atom-economical synthesis. Although isomerization reactions of unsaturated organic and organometallic compounds, such as alkenes, alkynes, and metal carbynes, have been achieved, those of metal vinylidene units that contain cumulated double bonds have never been reported. Herein, we inaugurally discovered isomerization reactions of metal vinylidene units via protonation and deprotonation reactions of metal carbenes. Experimental and theoretical investigations indicate that the electrical characteristics of substituents on the rings play a crucial role in controlling the formation of metal vinylidene units. The isomerization reactions of metal vinylidene units were driven by thermodynamic forces. Moreover, one of the angles at metal vinylidenes was found as 126.9°, representing the smallest angle in metal vinylidenes and the first cyclic 4d transition metal (Ru) vinylidene complex was successfully isolated. These investigations unveil novel structures and reactivity for metal vinylidenes, offering a fresh perspective on the isomerization reactions of unsaturated molecules containing cumulative unsaturated bonds.
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Affiliation(s)
- Xuejuan Zheng
- Shenzhen Grubbs Institute, Department of Chemistry, Guangming Advanced Research Institute, Southern University of Science and Technology Shenzhen 518055 China
| | - Fanping Huang
- Shenzhen Grubbs Institute, Department of Chemistry, Guangming Advanced Research Institute, Southern University of Science and Technology Shenzhen 518055 China
| | - Xinyuan Li
- Shenzhen Grubbs Institute, Department of Chemistry, Guangming Advanced Research Institute, Southern University of Science and Technology Shenzhen 518055 China
| | - Kaiyue Zhuo
- Shenzhen Grubbs Institute, Department of Chemistry, Guangming Advanced Research Institute, Southern University of Science and Technology Shenzhen 518055 China
| | - Dafa Chen
- Shenzhen Grubbs Institute, Department of Chemistry, Guangming Advanced Research Institute, Southern University of Science and Technology Shenzhen 518055 China
| | - Ming Luo
- Shenzhen Grubbs Institute, Department of Chemistry, Guangming Advanced Research Institute, Southern University of Science and Technology Shenzhen 518055 China
| | - Haiping Xia
- Shenzhen Grubbs Institute, Department of Chemistry, Guangming Advanced Research Institute, Southern University of Science and Technology Shenzhen 518055 China
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2
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Kleinpeter E, Koch A. Carbones - A Classification on the Magnetic Criterion. Chem Asian J 2024; 19:e202300826. [PMID: 37966046 DOI: 10.1002/asia.202300826] [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: 09/21/2023] [Revised: 11/13/2023] [Accepted: 11/13/2023] [Indexed: 11/16/2023]
Abstract
Carbones (carbodiphosphoranes, bent allenes and chalcogen-stabilized carbones) bear the same resonance contributor X+ -C2- -Y+ (X+ , Y+ =PR3 + , CR2 + , SR2 + , SeR2 + , S+ R2 =NR) and exhibit unique bonding and donating properties at the central carbon atom. A classification is given on basis of both the geometry and the magnetic properties (13 C chemical shift of the central carbon atom and the spatial magnetic properties, through-space NMR shieldings (TS NMRSs), actually the anisotropy effect or the ring current effect of aromatic species). TS NMRS values have been calculated using the GIAO perturbation method employing the nucleus independent chemical shift (NICS) concept and the results visualized as iso-chemical-shielding surfaces (ICSS) of various size and direction. The synergy of geometry (linear or bent, orthogonal or twisted structures) and NMR characteristics (extend of the high field shift of the central carbon atom, anisotropy effect of the allene-like C=C double bonds or the ball-like anisotropy effect of carbone-like central carbon atom) provides a comprehensive picture of the dominating resonance contributor.
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Affiliation(s)
- Erich Kleinpeter
- Chemisches Institut der Universität Potsdam, Karl-Liebknecht-Str. 24-25, D-14476, Potsdam (Golm), Germany
| | - Andreas Koch
- Chemisches Institut der Universität Potsdam, Karl-Liebknecht-Str. 24-25, D-14476, Potsdam (Golm), Germany
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3
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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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4
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Parvathy P, Parameswaran P. Inorganometallic allenes [(Mn(η 5-C 5H 5)(CO) 2) 2(μ-E)] (E = Si-Pb): bis-allylic anionic delocalisation similar to organometallic allene but differential σ-donation and π-backdonation. Phys Chem Chem Phys 2023; 25:26526-26537. [PMID: 37752826 DOI: 10.1039/d3cp03211f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/28/2023]
Abstract
The chemistry of heavy group-14 tetrel atoms is known to diverge from that of the lighter congener carbon. Here, we report the structure and bonding in inorganometallic allenes [(MnCp(CO)2)2(μ-E)] (2E, E = Si-Pb; Cp = η5-C5H5). These inorganometallic allenes are structurally similar to the lighter organometallic analog [(MnCp(CO)2)2(μ-C)] (2C). The bonding analysis of these compounds at the M06/def2-TZVPP//BP86/def2-SVP level of theory identifies a linear Mn-E-Mn spine with delocalised, mutually orthogonal π-systems across this back-bone. This results in a bis-allylic anionic bonding scenario. However, the strength of the Mn-E bonding is found to be weaker in these inorganometallic allenes. The energy decomposition analysis at the BP86/TZ2P//BP86/def2-SVP level of theory further reveals that the bonding in these compounds cannot be represented by one unique heuristic bonding model, but multiple bonding models. For all 2E (E = C-Pb), the Dewar-Chatt-Duncanson bonding model is one of the best bonding representations, where the central tetrel atom acts as a 4e- σ-donor and 4e- π-acceptor. The bonding analysis indicates that the carbon atom in the organometallic allene acts as a better π-acceptor than σ-donor, while the heavier tetrel atoms in the inorganometallic allenes are better σ-donors than π-acceptors. The npz-orbital is found to be a better σ-donor than the valence ns-orbital. However, when the bonding representation is changed to a traditional electron-sharing model, the contribution from the ns-orbital was found to be the largest in comparison to the interaction from the remaining three valence np-orbitals. It can be suggested that the ns-orbitals contribute more towards chemical bonding when participating via an electron-sharing interaction than a donor-acceptor interaction.
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Affiliation(s)
- Parameswaran Parvathy
- Department of Chemistry, National Institute of Technology Calicut, Kerala, 673601, India.
| | - Pattiyil Parameswaran
- Department of Chemistry, National Institute of Technology Calicut, Kerala, 673601, India.
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5
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Wanjari PJ, Rath A, Sathe RY, Bharatam PV. Identification of CYP3A4 inhibitors as potential anti-cancer agents using pharmacoinformatics approach. J Mol Model 2023; 29:156. [PMID: 37097473 DOI: 10.1007/s00894-023-05538-z] [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: 12/23/2022] [Accepted: 03/30/2023] [Indexed: 04/26/2023]
Abstract
Biguanide derivatives exhibit a wide variety of therapeutic applications, including anti-cancer effects. Metformin is an effective anti-cancer agent against breast cancer, lung cancer, and prostate cancer. In the crystal structure (PDB ID: 5G5J), it was found that metformin is found in the active site of CYP3A4, and the associated anti-cancer effect was explored. Taking clues from this work, pharmacoinformatics research has been carried out on a series of known and virtual biguanide, guanylthiourea (GTU), and nitreone derivatives. This exercise led to the identification of more than 100 species that exhibit greater binding affinity toward CYP3A4 in comparison to that of metformin. Selected six molecules were subjected to molecular dynamics simulations, and the results are presented in this work.
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Affiliation(s)
- Pravin J Wanjari
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar-160062, Punjab, India
| | - Asutosh Rath
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar-160062, Punjab, India
| | - Rohit Y Sathe
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar-160062, Punjab, India
| | - Prasad V Bharatam
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar-160062, Punjab, India.
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6
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Körner L, Ho LP, Puchta R, Stanger A, Tamm M. Dimorpholinoacetylene and Its Use for the Synthesis of Tetraaminocyclobutadiene Species. Chemistry 2022; 28:e202202737. [PMID: 36148808 PMCID: PMC9828195 DOI: 10.1002/chem.202202737] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Indexed: 01/12/2023]
Abstract
The new diaminoacetylene (DAA) dimorpholinoacetylene (3) was prepared from 1,1-dimorpholinoethene (1) by bromination to form the dibromoketene aminal 2, which upon lithiation afforded 3 through a Fritsch-Buttenberg-Wiechell rearrangement. Heating 3 at elevated temperatures resulted in a complete conversion into the dimer 1,1,2,4-tetramorpholino-1-buten-3-yne (4), which was used for the synthesis of four-membered cyclic bent allene (CBA) transition-metal complexes of the type [(CBA)MLn ] (5-7; MLn =AuCl, RhCl(COD), RhCl(CO)2 ; CBA=1,3,4,4-tetramorpholino-1,2-cyclobutadiene; COD=1,5-cyclooctadiene). The reaction of 3 with tetraethylammonium bromide gave 1,2,3,4-tetramorpholinocyclobutenylium bromide (8), which reacted with bromine to form 1,2,3,4-tetra(morpholino)cyclobutenediylium bis(tribromide) (9). Compound 9 represents the first fully characterized compound containing a tetraaminocyclobutadiene dication and displays a nearly planar C4 N4 core as shown by X-ray diffraction analysis. Detailed quantum chemical calculations were performed to assess the aromaticity of tetraaminocyclubutadiene dications by employing the Nucleus Independent Chemical Shift (NICS) method and current density analysis.
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Affiliation(s)
- Lukas Körner
- Institut für Anorganische und Analytische ChemieTechnische Universität BraunschweigHagenring 3038106BraunschweigGermany
| | - Luong Phong Ho
- Institut für Anorganische und Analytische ChemieTechnische Universität BraunschweigHagenring 3038106BraunschweigGermany
| | - Ralph Puchta
- Department Chemie und PharmazieFriedrich-Alexander Universität Erlangen-NürnbergEgerlandstr. 191058ErlangenGermany
| | - Amnon Stanger
- Schulich Department of Chemistry, TechnionHaifa32000Israel
| | - Matthias Tamm
- Institut für Anorganische und Analytische ChemieTechnische Universität BraunschweigHagenring 3038106BraunschweigGermany
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7
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Wanjari PJ, Saha N, Dubey G, Bharatam PV. Metal-free methods for the generation of benzimidazoles and 2-aminobenzimidazoles. Tetrahedron 2022. [DOI: 10.1016/j.tet.2022.133143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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8
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Breitwieser K, Bahmann H, Weiss R, Munz D. Gauging Radical Stabilization with Carbenes. Angew Chem Int Ed Engl 2022; 61:e202206390. [PMID: 35796423 PMCID: PMC9545232 DOI: 10.1002/anie.202206390] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Indexed: 11/29/2022]
Abstract
Carbenes, including N-heterocyclic carbene (NHC) ligands, are used extensively to stabilize open-shell transition metal complexes and organic radicals. Yet, it remains unknown, which carbene stabilizes a radical well and, thus, how to design radical-stabilizing C-donor ligands. With the large variety of C-donor ligands experimentally investigated and their electronic properties established, we report herein their radical-stabilizing effect. We show that radical stabilization can be understood by a captodative frontier orbital description involving π-donation to- and π-donation from the carbenes. This picture sheds a new perspective on NHC chemistry, where π-donor effects usually are assumed to be negligible. Further, it allows for the intuitive prediction of the thermodynamic stability of covalent radicals of main group- and transition metal carbene complexes, and the quantification of redox non-innocence.
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Affiliation(s)
- Kevin Breitwieser
- Coordination ChemistrySaarland UniversityCampus C4.166123SaarbrückenGermany
| | - Hilke Bahmann
- Physical and Theoretical ChemistrySaarland UniversityCampus B2.266123SaarbrückenGermany
| | - Robert Weiss
- Organische ChemieFriedrich-Alexander-Universität (FAU) Erlangen-NürnbergHenkestr. 4291054ErlangenGermany
| | - Dominik Munz
- Coordination ChemistrySaarland UniversityCampus C4.166123SaarbrückenGermany
- Inorganic and General ChemistryFriedrich-Alexander-Universität (FAU) Erlangen-NürnbergEgerlandstr. 191058ErlangenGermany
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9
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Breitwieser K, Bahmann H, Weiss R, Munz D. Gauging Radical Stabilization with Carbenes. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202206390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Kevin Breitwieser
- Saarland University: Universitat des Saarlandes Coordination Chemistry GERMANY
| | - Hilke Bahmann
- Saarland University: Universitat des Saarlandes Theoretical Chemistry GERMANY
| | - Robert Weiss
- FAU Erlangen Nuremberg: Friedrich-Alexander-Universitat Erlangen-Nurnberg Organic Chemistry GERMANY
| | - Dominik Munz
- Universitat des Saarlandes Inorganic Chemistry: Coordination Chemistry Campus C 4.1 66123 Saarbrücken GERMANY
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10
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Garner MH, Laplaza R, Corminboeuf C. Helical versus linear Jahn–Teller distortions in allene and spiropentadiene radical cations. Phys Chem Chem Phys 2022; 24:26134-26143. [DOI: 10.1039/d2cp03544h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
The allene radical cation can be stabilized both by Jahn–Teller distortion of the bond lengths and by torsion of the end-groups.
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Affiliation(s)
- Marc H. Garner
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique federale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Ruben Laplaza
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique federale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Clemence Corminboeuf
- Laboratory for Computational Molecular Design, Institute of Chemical Sciences and Engineering, Ecole Polytechnique federale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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11
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Savic VM, Jovanovic MD, Petkovic MR. Polycyclic Compounds from Allenes via Palladium-Mediated Intramolecular Carbopalladation/Nucleophilic Substitution Cascade Processes. SYNTHESIS-STUTTGART 2021. [DOI: 10.1055/s-0040-1705994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
AbstractIn recent decades transition metals have made a substantial contribution to the development of novel synthetic processes, with palladium catalysis being, arguably, at the forefront of this research. The efficiency of Pd-promoted C–C or C–X bond formation along with a variety of other transformations renders this metal an indispensable tool in synthetic organic chemistry. Of particular interest are Pd-catalysed multicomponent cascade reactions as they often allow the creation of complex structures from relatively simple starting materials, mimicking in this sense biochemical processes. Allenes as partners in Pd-promoted cascades involving carbopalladation/nucleophilic substitutions have been extensively studied in recent years. Many tactical variants have been explored showing a high level of efficiency and chemoselectivity with predictable outcomes. This short review is focused on intramolecular processes of this type because they provide access to relatively complex polycyclic products, possessing structural features often found in natural products and related compounds. Various approaches are discussed with the intention to demonstrate their applicability and synthetic potential.1 Introduction2 Intramolecular Palladium-Promoted Cascades of Allenes3 Class I Cyclisations4 Class II Cyclisations5 Class III Cyclisations6 Class IV Cyclisations7 Conclusion
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12
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Loan HP, Bui TQ, My TTA, Hai NTT, Quang DT, Tat PV, Hiep DT, Trung NT, Quy PT, Nhung NTA. In-Depth Investigation of a Donor-Acceptor Interaction on the Heavy-Group-14@Group-13-Diyls in Transition-Metal Tetrylone Complexes: Structure, Bonding, and Property. ACS OMEGA 2020; 5:21271-21287. [PMID: 32875264 PMCID: PMC7450610 DOI: 10.1021/acsomega.0c03237] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 08/04/2020] [Indexed: 06/11/2023]
Abstract
Stabilization for tetrylone complexes, which carry ylidone(0) ligands [(CO)5W-X (YCp*)2] (X = Ge, Sn, Pb; Y = B-Tl), has become an active theoretical research because of their promising application. Structure, bonding, and quantum properties of the transition-metal donor-acceptor complexes were theoretically investigated at the level of theory BP86 with several types of basis sets including SVP, TZVPP, and TZ2P+. The optimized structures reveal that all ligands X (YCp*)2 are strongly bonded in tilted modes to the metal fragment W(CO)5, and Cp* rings are mainly η5-bonded to atom X. DFT-based bonding analysis results in an implication that the stability of W-X bond strength primarily stems from the donation (CO)5W ← X(YCp*)2 formed by both σ- and π-bondings and the electrostatic interaction ΔE elstat. The W-X bond possesses a considerable polarizability toward atom X, and analysis on its hybridization is either sp2-characteristic or mainly p-characteristic. EDA-NOCV-based results further imply that the ligands XY perform as significant σ-donors but minor π-donors. The visual simulations of NOCV pairs and the deformation densities assemble a comprehensive summary on different components of the chemical bond via σ- and π-types in the complexes. This work contributes to the literature as an in-depth overview on predicted molecular structures and quantum parameters of the complexes [(CO)5W-X(YCp*)2] (X = Ge, Sn, Pb; Y = B-Tl), conducive to either further theoretical reference or extending experimental research.
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Affiliation(s)
- Huynh
Thi Phuong Loan
- Department
of Chemistry, University of Sciences, Hue
University, Hue City 530000, Vietnam
| | - Thanh Q. Bui
- Department
of Chemistry, University of Sciences, Hue
University, Hue City 530000, Vietnam
| | - Tran Thi Ai My
- Department
of Chemistry, University of Sciences, Hue
University, Hue City 530000, Vietnam
| | - Nguyen Thi Thanh Hai
- Department
of Chemistry, University of Sciences, Hue
University, Hue City 530000, Vietnam
| | - Duong Tuan Quang
- Department
of Chemistry, University of Education, Hue
University, Hue City 530000, Vietnam
| | - Pham Van Tat
- Institute
of Development and Applied Economics, Hoa
Sen University, Ho Chi
Minh City 700000, Vietnam
| | - Dang Tan Hiep
- Office
of Academic Affairs, HCMC University of
Food Industry, Ho Chi Minh City 700000, Vietnam
| | - Nguyen Tien Trung
- Laboratory
of Computational Chemistry and Modeling, Faculty of Natural Sciences, Quy Nhon University, Quy Nhon City 590000, Vietnam
| | - Phan Tu Quy
- Department
of Natural Sciences & Technology, Tay
Nguyen University, Buon Ma
Thuot City 630000, Vietnam
| | - Nguyen Thi Ai Nhung
- Department
of Chemistry, University of Sciences, Hue
University, Hue City 530000, Vietnam
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13
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Kleinpeter E, Koch A. Bent Allenes or Di-1,3-betaines-An Answer Given on the Magnetic Criterion. J Phys Chem A 2020; 124:3180-3190. [PMID: 32223167 DOI: 10.1021/acs.jpca.0c01392] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The spatial magnetic properties, through-space NMR shieldings (TSNMRS), of bent allene 1, the corresponding C-extended 1,3-butadiene derivative 2, and a number of related compounds 3-20 have been calculated using the gauge-independent atomic orbital perturbation method, employing the nucleus-independent chemical shift concept and visualized as isochemical shielding surfaces of various sizes and directions. Prior to that, both structures and 13C chemical shifts were calculated and compared with available experimental bond lengths and δ(13C)/ppm values (also, as a quality criterion for the computed structures). Bond lengths, the δ(13C)/ppm, and the TSNMRS values are employed to qualify and quantify the electronic structure of the studied compounds in terms of dative or classical electron-sharing bonds.
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Affiliation(s)
- Erich Kleinpeter
- Institut für Chemie, Universität Potsdam, Karl-Liebknecht-Str. 24-25, D-14476 Potsdam (Golm), Germany
| | - Andreas Koch
- Institut für Chemie, Universität Potsdam, Karl-Liebknecht-Str. 24-25, D-14476 Potsdam (Golm), Germany
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14
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Chan SC, Ang ZZ, Gupta P, Ganguly R, Li Y, Ye S, England J. Carbodicarbene Ligand Redox Noninnocence in Highly Oxidized Chromium and Cobalt Complexes. Inorg Chem 2020; 59:4118-4128. [PMID: 32101411 DOI: 10.1021/acs.inorgchem.0c00153] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Carbodicarbenes (CDCs) possess two lone pairs of electrons on their central carbone C atom (Ccarbone). Coordination to a transition metal via a σ bond leaves one pair of electrons with appropriate symmetry for π donation to the metal. However, the high energy of the latter also renders the CDC ligand potentially redox-active. Herein, we explore these alternatives in the redox series [Cr(L)2]n+ and [Co(L)2]n+ (n = 2-5), where L is a tridentate ligand comprised of a central CDC and two flanking pyridine donors. To this end, all members of both redox series were synthesized and their electronic structures were investigated by using a combination of 1H NMR, Evans' NMR, IR, UV-vis, and EPR spectroscopies, SQUID magnetometry, X-ray crystallography, and density functional theory studies. Whereas [CoII(L)2]2+ is a straightforward low-spin (S = 1/2) cobalt(II) complex, the corresponding chromium complex was found to feature an electronic structure that is intermediate between the two limiting resonance forms [CrIII(L•-)(L)]2+ and [CrII(L)2]2+. In the case of the tri-, tetra-, and pentacationic complexes, the qualitatively identical electronic structures [MIII(L)2]3+, [MIII(L•+)(L)]4+, and [MIII(L•+)2]5+ were observed for both metals. Thus, the metal ions retain a 3+ oxidation state throughout, and the higher redox states contain oxidized ligands. The majority of the unpaired spin on the cation radical ligands was calculated to be localized in π-symmetry orbitals on the coordinated Ccarbone atoms. Analogous behavior was previously reported for the corresponding iron redox series and, as such, redox noninnocence in oxidized CDC and, more broadly, carbone complexes is likely widely accessible.
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Affiliation(s)
- Siu-Chung Chan
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University (NTU), 21 Nanyang Link, 637371, Singapore
| | - Zhi Zhong Ang
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University (NTU), 21 Nanyang Link, 637371, Singapore
| | - Puneet Gupta
- Max-Plank-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, Mülheim an der Ruhr D-45470, Germany
| | - Rakesh Ganguly
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University (NTU), 21 Nanyang Link, 637371, Singapore
| | - Yongxin Li
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University (NTU), 21 Nanyang Link, 637371, Singapore
| | - Shengfa Ye
- Max-Plank-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, Mülheim an der Ruhr D-45470, Germany.,State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Jason England
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University (NTU), 21 Nanyang Link, 637371, Singapore
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15
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Saeidian H, Mirjafary Z. Engineering non-ionic carbon super- and hyperbases by a computational DFT approach: substituted allenes have unprecedented cation affinities. NEW J CHEM 2020. [DOI: 10.1039/d0nj02207a] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
DFT calculations reveal that allenes substituted by a cyclopropene or a methylenecyclopropene group, offer suitable scaffolds for tailoring powerful carbon bases. The protonation at C(sp) site provide superbases with PAs = 879–1218 kJ mol−1.
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Affiliation(s)
- Hamid Saeidian
- Department of Science
- Payame Noor University (PNU)
- Tehran
- Iran
| | - Zohreh Mirjafary
- Department of Chemistry
- Science and Research Branch
- Islamic Azad University
- Tehran
- Iran
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16
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Hackl L, Petrov AR, Bannenberg T, Freytag M, Jones PG, Tamm M. Dimerisation of Dipiperidinoacetylene: Convenient Access to Tetraamino-1,3-Cyclobutadiene and Tetraamino-1,2-Cyclobutadiene Metal Complexes. Chemistry 2019; 25:16148-16155. [PMID: 31625641 PMCID: PMC6973143 DOI: 10.1002/chem.201904726] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Indexed: 01/24/2023]
Abstract
The reaction of 1,2-dipiperidinoacetylene (1) with 0.5 equivalents of SnCl2 or GeCl2 ⋅dioxane afforded the 1,2,3,4-tetrapiperidino-1,3-cyclobutadiene tin and germanium dichloride complexes 2 a and 2 b, respectively. A competing redox reaction was observed with excess amounts of SnCl2 , which produced a tetrapiperidinocyclobutadiene dication with two trichlorostannate(II) counterions. Heating neat 1 to 110 °C for 16 h cleanly produced the dimer 1,3,4,4-tetrapiperidino-3-buten-1-yne (3); its reaction with stoichiometric amounts of SnCl2 or GeCl2 ⋅dioxane furnished the 1,3,4,4-tetrapiperidino-1,2-cyclobutadiene tin and germanium dichloride complexes 4 a and 4 b, respectively. Transition-metal complexes containing this novel four-membered cyclic bent allene (CBA) ligand were prepared by reaction of 3 with [(tht)AuCl], [RhCl(CO)2 ]2 , and [(Me3 N)W(CO)5 ] to form [(CBA)AuCl] (5), [(CBA)RhCl(CO)2 ] (6), and [(CBA)W(CO)5 ] (7). The molecular structures of all compounds 2-7 were determined by X-ray diffraction analyses, and density functional theory (DFT) calculations were carried out to rationalise the formation of 3 and 4 a.
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Affiliation(s)
- Ludwig Hackl
- Institut für Anorganische und Analytische ChemieTechnische Universität BraunschweigHagenring 3038106BraunschweigGermany
| | - Alex R. Petrov
- Institut für Anorganische und Analytische ChemieTechnische Universität BraunschweigHagenring 3038106BraunschweigGermany
| | - Thomas Bannenberg
- Institut für Anorganische und Analytische ChemieTechnische Universität BraunschweigHagenring 3038106BraunschweigGermany
| | - Matthias Freytag
- Institut für Anorganische und Analytische ChemieTechnische Universität BraunschweigHagenring 3038106BraunschweigGermany
| | - Peter G. Jones
- Institut für Anorganische und Analytische ChemieTechnische Universität BraunschweigHagenring 3038106BraunschweigGermany
| | - Matthias Tamm
- Institut für Anorganische und Analytische ChemieTechnische Universität BraunschweigHagenring 3038106BraunschweigGermany
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17
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Marín-Luna M, Nieto Faza O, Silva López C. Gold-Catalyzed Homogeneous (Cyclo)Isomerization Reactions. Front Chem 2019; 7:296. [PMID: 31139614 PMCID: PMC6527766 DOI: 10.3389/fchem.2019.00296] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 04/11/2019] [Indexed: 01/09/2023] Open
Abstract
Gold is currently one of the most used metals in organometallic catalysis. The ability of gold to activate unsaturated groups in different modes, together with its tolerance to a wide range of functional groups and reaction conditions, turns gold-based complexes into efficient and highly sought after catalysts. Natural products and relevant compounds with biological and pharmaceutical activity are often characterized by complex molecular structures. (Cyclo)isomerization reactions are often a useful strategy for the generation of this molecular complexity from synthetically accessible reactants. In this review, we collect the most recent contributions in which gold(I)- and/or gold(III)-catalysts mediate intramolecular (cyclo)isomerization transformations of unsaturated species, which commonly feature allene or alkyne motifs, and organize them depending on the substrate and the reaction type.
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Affiliation(s)
- Marta Marín-Luna
- Departamento de Química Orgánica, Universidade de Vigo, Vigo, Spain
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18
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Radić N, Maksić ZB. Carbon Atom as an Extremely Strong Nucleophilic and Electrophilic Center: Dendritic Allenes Are Powerful Organic Proton and Hydride Sponges. J Org Chem 2019; 84:2425-2438. [PMID: 30747532 DOI: 10.1021/acs.joc.8b02641] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Gas-phase proton affinities (PAs) and hydride affinities (HAs) of organic bases possessing an allene moiety and substituted with methyl, dimethylamino, cyano, and vinyl substituents were examined with the B3LYP/6-311+G(2df,p)//B3LYP/6-31G(d) model. It was shown that a number of superbases and hyperbases can be obtained, as well as the potent hydride sponges. Methyl or dimethylamino substituents increased the proton affinity of the parent molecule, and the cyano substituents increased its hydride affinity. When the vinyl substituents are placed on allene, both the hydride and the proton affinities increased. A disubstituted allene with two dimethylamino groups is the smallest studied superbase, whereas the allene tetrasubstituted with four vinyl groups gives the smallest superbase possessing only alkene substituents. By introducing the vinyl group as a repeating subunit, one can obtain dendritic structures with the investigated substituents determining its properties. By changing the dimethylamino with the cyano group, a dendrimeric molecule can change from a hyperbase with a proton affinity of 324.6 kcal mol-1 to a very strong hydride ion acceptor with a hydride affinity of 205.4 kcal mol-1, while possessing the same proton or hydride ion attachment site.
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Affiliation(s)
- Nena Radić
- Computational Organic Chemistry and Biochemistry Group, Division of Organic Chemistry and Biochemistry , Ruđer Bošković Institute , 10000 Zagreb , Croatia
| | - Zvonimir B Maksić
- Computational Organic Chemistry and Biochemistry Group, Division of Organic Chemistry and Biochemistry , Ruđer Bošković Institute , 10000 Zagreb , Croatia
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19
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Bhagat S, Arfeen M, Das G, Patel N, Bharatam PV. Electronic and ligating properties of carbocyclic carbenes: A theoretical investigation. J Comput Chem 2018; 40:726-733. [PMID: 30549074 DOI: 10.1002/jcc.25756] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Revised: 10/27/2018] [Accepted: 11/01/2018] [Indexed: 11/05/2022]
Abstract
Carbocyclic carbenes (CCCs) are a class of nucleophilic carbenes which are very similar to N-heterocyclic carbenes (NHCs) in terms of their reactivity, but they do not contain a stabilizing heteroatom in their cyclic ring system. In this study, 17 representative known CCCs and 34 newly designed CCCs are evaluated using quantum chemical methods, and the results are compared in terms of their stability, nucleophilicity, and proton affinity (PA) parameters. The results are divided on the basis of ring size of the known and reported CCCs. The stability, nucleophilicity, PA, complexation energy, and bond strength-related parameters were estimated using M06/6-311++G(d,p) method. The results indicated that the CCCs known in the literature are strong σ-electron donating species and have considerable π-accepting properties. This study led to the design and identification of a few new CCCs with dimethylamine and diaminomethynyl substituents which can be singlet stable and are substantially nucleophilic. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Shweta Bhagat
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Mohali, Punjab, 160062, India
| | - Minhajul Arfeen
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Mohali, Punjab, 160062, India
| | - Gourav Das
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Mohali, Punjab, 160062, India
| | - Neha Patel
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Mohali, Punjab, 160062, India
| | - Prasad V Bharatam
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Mohali, Punjab, 160062, India
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20
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Purushothaman I, De S, Parameswaran P. Different Donor-Acceptor Interactions of Carbene Ligands in Heteroleptic Divalent Group 14 Compounds, LEL′ (E=C-Sn; L=N-Heterocyclic Carbene; L′=Cyclic Alkyl(Amino) Carbene). Chemistry 2018; 24:3816-3824. [DOI: 10.1002/chem.201705719] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Indu Purushothaman
- Department of Chemistry; National Institute of Technology Calicut; NIT Campus P.O., Kozhikode 673 601 Kerala India
| | - Susmita De
- Department of Chemistry; National Institute of Technology Calicut; NIT Campus P.O., Kozhikode 673 601 Kerala India
- Department of Applied Chemistry; Cochin University of Science and Technology; Trikakkara Cochin 682022, Kerala India
| | - Pattiyil Parameswaran
- Department of Chemistry; National Institute of Technology Calicut; NIT Campus P.O., Kozhikode 673 601 Kerala India
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21
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Cumine F, Young A, Reissig HU, Tuttle T, Murphy JA. A Computational Study of Anionic Alkoxide-Allene and Amide-Allene Cyclizations. European J Org Chem 2017. [DOI: 10.1002/ejoc.201701381] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Florimond Cumine
- Department of Pure and Applied Chemistry; University of Strathclyde; 295 Cathedral Street G1 1XL Glasgow United Kingdom
| | - Allan Young
- Department of Pure and Applied Chemistry; University of Strathclyde; 295 Cathedral Street G1 1XL Glasgow United Kingdom
| | - Hans-Ulrich Reissig
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustr. 3 14195 Berlin Germany
| | - Tell Tuttle
- Department of Pure and Applied Chemistry; University of Strathclyde; 295 Cathedral Street G1 1XL Glasgow United Kingdom
| | - John A. Murphy
- Department of Pure and Applied Chemistry; University of Strathclyde; 295 Cathedral Street G1 1XL Glasgow United Kingdom
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22
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Okala Amombo GM, Flögel O, Kord Daoroun Kalai S, Schoder S, Warzok U, Reissig HU. Efficient Syntheses of 2,5-Dihydropyrroles, Pyrrolidin-3-ones, and Electron-Rich Pyrroles fromN-Tosylimines and Lithiated Alkoxyallenes. European J Org Chem 2017. [DOI: 10.1002/ejoc.201700073] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Ghislaine Marlyse Okala Amombo
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustr. 3 14195 Berlin Germany
- Fachrichtung Chemie und Lebensmittelchemie; Technische Universität Dresden; 01062 Dresden Germany
| | - Oliver Flögel
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustr. 3 14195 Berlin Germany
| | | | - Stefan Schoder
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustr. 3 14195 Berlin Germany
| | - Ulrike Warzok
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustr. 3 14195 Berlin Germany
| | - Hans-Ulrich Reissig
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustr. 3 14195 Berlin Germany
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23
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Morosaki T, Fujii T. Recent Advances in Heteroatom-Stabilized Carbones and Their Metal Complexes. ADVANCES IN ORGANOMETALLIC CHEMISTRY 2017. [DOI: 10.1016/bs.adomc.2017.08.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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24
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Chen Q, Liu X, Guo F, Chen Z. An unexpected rearrangement of pyrazolium halides based on N–N bond cleavage: synthesis of 1,2-dihydropyrimidines. Chem Commun (Camb) 2017; 53:6792-6795. [DOI: 10.1039/c7cc02525d] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An unexpected rearrangement of pyrazolium halides was observed, presenting an efficient approach for the synthesis of 1,2-dihydroquinazolines under mild conditions.
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Affiliation(s)
- Qian Chen
- State Key Laboratory of Urban Water Resource and Environment
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage
- School of Chemistry and Chemical Engineering
- Harbin Institute of Technology
- Harbin
| | - Xiaoshuang Liu
- State Key Laboratory of Urban Water Resource and Environment
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage
- School of Chemistry and Chemical Engineering
- Harbin Institute of Technology
- Harbin
| | - Fang Guo
- State Key Laboratory of Urban Water Resource and Environment
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage
- School of Chemistry and Chemical Engineering
- Harbin Institute of Technology
- Harbin
| | - Zhonglin Chen
- School of Municipal Environmental Engineering
- Harbin Institute of Technology
- Harbin
- China
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25
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Alcaide B, Almendros P, Cembellín S, Fernández I, Martínez Del Campo T. Metal-Catalyzed Cyclization Reactions of 2,3,4-Trien-1-ols: A Joint Experimental-Computational Study. Chemistry 2016; 22:11667-76. [PMID: 27383332 DOI: 10.1002/chem.201601838] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Indexed: 01/26/2023]
Abstract
Controlled preparation of tri- and tetrasubstituted furans, as well as carbazoles has been achieved through chemo- and regioselective metal-catalyzed cyclization reactions of cumulenic alcohols. The gold- and palladium-catalyzed cycloisomerization reactions of cumulenols, including indole-tethered 2,3,4-trien-1-ols, to trisubstituted furans was effective, due to a 5-endo-dig oxycyclization by attack of the hydroxy group onto the central cumulene double bond. In contrast, palladium-catalyzed heterocyclization/coupling reactions with 3-bromoprop-1-enes furnished tetrasubstituted furans. Also studied was the palladium-catalyzed cyclization/coupling sequence involving protected indole-tethered 2,3,4-trien-1-ols and 3-bromoprop-1-enes that exclusively generated trisubstituted carbazole derivatives. These results could be explained through a selective 6-endo-dig cumulenic hydroarylation, followed by aromatization. DFT calculations were carried out to understand this difference in reactivity.
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Affiliation(s)
- Benito Alcaide
- Grupo de Lactamas y Heterociclos Bioactivos, Departamento de Química Orgánica I, Unidad Asociada al CSIC, Facultad de Química, Universidad Complutense de Madrid, 28040, Madrid, Spain.
| | - Pedro Almendros
- Instituto de Qímica General, Consejo Superior de Investigaciones Científicas, IQOG-CSIC, Juan de la Cierva 3, 28006, Madrid, Spain.
| | - Sara Cembellín
- Grupo de Lactamas y Heterociclos Bioactivos, Departamento de Química Orgánica I, Unidad Asociada al CSIC, Facultad de Química, Universidad Complutense de Madrid, 28040, Madrid, Spain
| | - Israel Fernández
- Departamento de Química Orgánica I, Facultad de Química, Universidad Complutense de Madrid, 28040, Madrid, Spain.
| | - Teresa Martínez Del Campo
- Grupo de Lactamas y Heterociclos Bioactivos, Departamento de Química Orgánica I, Unidad Asociada al CSIC, Facultad de Química, Universidad Complutense de Madrid, 28040, Madrid, Spain
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26
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Pranckevicius C, Liu LL, Bertrand G, Stephan DW. Synthesis of a Carbodicyclopropenylidene: A Carbodicarbene based Solely on Carbon. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201600765] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
| | - Liu Leo Liu
- Joint UCSD-CNRS Research Chemistry Laboratory (UMI 3555) Department of Chemistry and Biochemistry University of California San Diego La Jolla CA 92093-0343 USA
| | - Guy Bertrand
- Joint UCSD-CNRS Research Chemistry Laboratory (UMI 3555) Department of Chemistry and Biochemistry University of California San Diego La Jolla CA 92093-0343 USA
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27
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Pranckevicius C, Liu LL, Bertrand G, Stephan DW. Synthesis of a Carbodicyclopropenylidene: A Carbodicarbene based Solely on Carbon. Angew Chem Int Ed Engl 2016; 55:5536-40. [PMID: 27028936 DOI: 10.1002/anie.201600765] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Indexed: 11/11/2022]
Abstract
The first carbodicarbene stabilized by flanking cyclopropenylidenes is reported. Tetraphenylcarbodicyclopropenylidene (2) is accessed by deprotonation of the corresponding triafulvene cyclopropenium salt, and has been spectroscopically characterized in [D8 ]THF solution at -60 °C. Main-group and transition-metal complexes of 2 have been accessed, and have revealed the high sigma donating ability, and exclusive η(1) binding of this neutral all carbon ligand. Variable temperature NMR spectroscopy studies reveal varying degrees of free rotation in the flanking cyclopropenylidene groups of 2 in its coordination compounds.
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Affiliation(s)
- Conor Pranckevicius
- Department of Chemistry, University of Toronto, Toronto, ON, M5S 3H6, Canada
| | - Liu Leo Liu
- Joint UCSD-CNRS Research Chemistry Laboratory (UMI 3555), Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA, 92093-0343, USA
| | - Guy Bertrand
- Joint UCSD-CNRS Research Chemistry Laboratory (UMI 3555), Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA, 92093-0343, USA
| | - Douglas W Stephan
- Department of Chemistry, University of Toronto, Toronto, ON, M5S 3H6, Canada.
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28
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Margetić D, Antol I. A DFT study of endocyclic allenes: unprecedentedly superbasic hydrocarbons. NEW J CHEM 2016. [DOI: 10.1039/c6nj00623j] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Extremely high basicities were predicted for allenes incorporated in seven-membered rings.
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Affiliation(s)
| | - Ivana Antol
- Ruđer Bošković Institute
- HR-10002 Zagreb
- Croatia
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29
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Hornung J, Hübner O, Kaifer E, Himmel HJ. Bent and twisted: the electronic structure of 2-azapropenylium ions obtained by guanidine oxidation. RSC Adv 2016. [DOI: 10.1039/c6ra04494h] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
New bis-2-azapropenylium ions are obtained by oxidation of guanidino-substituted aromatic compounds.
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Affiliation(s)
- Julius Hornung
- Anorganisch-Chemisches Institut
- Ruprecht-Karls-Universität Heidelberg
- 69120 Heidelberg
- Germany
| | - Olaf Hübner
- Anorganisch-Chemisches Institut
- Ruprecht-Karls-Universität Heidelberg
- 69120 Heidelberg
- Germany
| | - Elisabeth Kaifer
- Anorganisch-Chemisches Institut
- Ruprecht-Karls-Universität Heidelberg
- 69120 Heidelberg
- Germany
| | - Hans-Jörg Himmel
- Anorganisch-Chemisches Institut
- Ruprecht-Karls-Universität Heidelberg
- 69120 Heidelberg
- Germany
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30
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Vanitcha A, Damelincourt C, Gontard G, Vanthuyne N, Mouriès-Mansuy V, Fensterbank L. Bis-phosphine allene ligand: coordination chemistry and preliminary applications in catalysis. Chem Commun (Camb) 2016; 52:6785-8. [DOI: 10.1039/c6cc02316a] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A 1,3-bis-diphenylphosphine allene provided new coordination complexes with palladium, platinum and gold salts. The dinuclear gold(i) complex gave promising results in asymmetric catalysis.
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Affiliation(s)
- Avassaya Vanitcha
- Sorbonne Universités UPMC Univ Paris 06
- CNRS
- UMR 8232
- Institut Parisien de Chimie Moléculaire
- F-75005 Paris
| | - Cecilia Damelincourt
- Sorbonne Universités UPMC Univ Paris 06
- CNRS
- UMR 8232
- Institut Parisien de Chimie Moléculaire
- F-75005 Paris
| | - Geoffrey Gontard
- Sorbonne Universités UPMC Univ Paris 06
- CNRS
- UMR 8232
- Institut Parisien de Chimie Moléculaire
- F-75005 Paris
| | - Nicolas Vanthuyne
- Aix-Marseille Université
- Centrale Marseille
- CNRS
- iSm2 UMR 7313
- Marseille
| | - Virginie Mouriès-Mansuy
- Sorbonne Universités UPMC Univ Paris 06
- CNRS
- UMR 8232
- Institut Parisien de Chimie Moléculaire
- F-75005 Paris
| | - Louis Fensterbank
- Sorbonne Universités UPMC Univ Paris 06
- CNRS
- UMR 8232
- Institut Parisien de Chimie Moléculaire
- F-75005 Paris
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31
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Bharatam PV, Arfeen M, Patel N, Jain P, Bhatia S, Chakraborti AK, Khullar S, Gupta V, Mandal SK. Design, Synthesis, and Structural Analysis of Divalent N(I) Compounds and Identification of a New Electron-Donating Ligand. Chemistry 2015; 22:1088-96. [PMID: 26615987 DOI: 10.1002/chem.201503618] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Indexed: 11/09/2022]
Abstract
The dative-bond representation (L→E) in compounds with main group elements (E) has triggered extensive debate in the recent past. The scope and limits of this nonclassical coordination bond warrant comprehensive exploration. Particularly compounds with (L→N←L')(+) arrangement are of special interest because of their therapeutic importance. This work reports the design and synthesis of novel chemical species with the general structural formula (L→N←L')(+) carrying the unusual ligand cyclohexa-2,5-diene-4-(diaminomethynyl)-1-ylidene. Four species belonging to the (L→N←L')(+) class carrying this unconventional ligand were synthesized. Quantum chemical and X-ray diffraction analyses showed that the electronic and geometric parameters are consistent with those of already reported divalent N(I) compounds. The molecular orbital analysis, geometric parameters, and spectral data clearly support the L→N and N←L' interactions in these species. The newly identified ligand has the properties of a reactive carbene and high nucleophilicity.
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Affiliation(s)
- Prasad V Bharatam
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar -, 160 062, Punjab, India.
| | - Minhajul Arfeen
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar -, 160 062, Punjab, India
| | - Neha Patel
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar -, 160 062, Punjab, India
| | - Priyanka Jain
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar -, 160 062, Punjab, India
| | - Sonam Bhatia
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar -, 160 062, Punjab, India
| | - Asit K Chakraborti
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar -, 160 062, Punjab, India.
| | - Sadhika Khullar
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER), Mohali, Sector 81, S.A.S. Nagar -, 140 308, Punjab, India
| | - Vijay Gupta
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER), Mohali, Sector 81, S.A.S. Nagar -, 140 308, Punjab, India
| | - Sanjay K Mandal
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER), Mohali, Sector 81, S.A.S. Nagar -, 140 308, Punjab, India.
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Nakanowatari S, Ackermann L. Ruthenium(II)‐Catalyzed CH Functionalizations with Allenes: Versatile Allenylations and Allylations. Chemistry 2015; 21:16246-51. [DOI: 10.1002/chem.201502785] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Indexed: 12/13/2022]
Affiliation(s)
- Sachiyo Nakanowatari
- Institut für Organische und Biomolekulare Chemie, Georg‐August‐Universität Göttingen, Tammannstrasse 2, 37077 Göttingen (Germany)
| | - Lutz Ackermann
- Institut für Organische und Biomolekulare Chemie, Georg‐August‐Universität Göttingen, Tammannstrasse 2, 37077 Göttingen (Germany)
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33
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Pranckevicius C, Fan L, Stephan DW. Cyclic bent allene hydrido-carbonyl complexes of ruthenium: highly active catalysts for hydrogenation of olefins. J Am Chem Soc 2015; 137:5582-9. [PMID: 25855868 DOI: 10.1021/jacs.5b02203] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A new family of ruthenium complexes bearing the carbodicarbene-type ligand "cyclic bent allene" (CBA) have been synthesized from the common precursor RuHCl(CO)(PPh3)3. Complexes were evaluated for catalytic activity in the room-temperature hydrogenation of unactivated olefins and were found to be significantly more active than known ruthenium hydrido-carbonyl phosphine or NHC complexes. In particular, RuH(OSO2CF3)(CO)(SIMes)(CBA) was found to be among the most active hydrogenation catalysts, achieving comparable activity to Crabtree's catalyst in the hydrogenation of unactivated trisubstituted olefins and superior activity in the hydrogenation of styrene derivatives in side-by-side catalytic runs. RuH(OSO2CF3)(CO)(SIMes)(CBA) was also found to be highly active in olefin selective hydrogenation in the presence of a variety of unsaturated functional groups, and can achieve exceptional diastereoselectivity in functional-group-directed hydrogenations at very low catalyst loadings.
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Affiliation(s)
- Conor Pranckevicius
- Department of Chemistry, University of Toronto. Toronto, Ontario M5S 3H6, Canada
| | - Louie Fan
- Department of Chemistry, University of Toronto. Toronto, Ontario M5S 3H6, Canada
| | - Douglas W Stephan
- Department of Chemistry, University of Toronto. Toronto, Ontario M5S 3H6, Canada
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De Proft F, Broeckaert L, Turek J, Růžička A, Willem R. Reactivity of low-oxidation state tin compounds: an overview of the benefits of combining DFT Theory and experimental NMR spectroscopy. CAN J CHEM 2014. [DOI: 10.1139/cjc-2013-0521] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The reactivity and complexation properties of dicoordinated Sn(II) and Sn(0) compounds are reviewed. The (dominant) electrophilicity of the stannylenes was confirmed and quantified through density functional theory (DFT) based reactivity indices. For these compounds, combining theoretical DFT calculations and experimental nuclear magnetic resonance (NMR) spectroscopic results has evidenced their potential to undergo π-complexation from aromatic π clouds in addition to significantly stronger σ-complexation. Moreover, their potential as Lewis bases was scrutinized in their interactions and reactions with iron and tungsten carbonyl Lewis acids. Finally, a prospective comparison of the reactivity of divalent stannylenes and stannylones, with a 0 oxidation state at the Sn atom, is presented.
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Affiliation(s)
- Frank De Proft
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
| | - Lies Broeckaert
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
| | - Jan Turek
- Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, 53210 Pardubice, Czech Republic
| | - Aleš Růžička
- Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, 53210 Pardubice, Czech Republic
| | - Rudolph Willem
- Department of Materials and Chemistry (MACH), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
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35
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Bhatia S, Bharatam PV. Possibility of the Existence of Donor–Acceptor Interactions in Bis(azole)amines: An Electronic Structure Analysis. J Org Chem 2014; 79:4852-62. [DOI: 10.1021/jo402862r] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Sonam Bhatia
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S. A. S.
Nagar, Punjab 160 062, India
| | - Prasad V. Bharatam
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S. A. S.
Nagar, Punjab 160 062, India
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36
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Niepötter B, Herbst-Irmer R, Kratzert D, Samuel PP, Mondal KC, Roesky HW, Jerabek P, Frenking G, Stalke D. Experimental Charge Density Study of a Silylone. Angew Chem Int Ed Engl 2014; 53:2766-70. [DOI: 10.1002/anie.201308609] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 10/31/2013] [Indexed: 11/06/2022]
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37
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Niepötter B, Herbst-Irmer R, Kratzert D, Samuel PP, Mondal KC, Roesky HW, Jerabek P, Frenking G, Stalke D. Experimentelle Elektronendichteuntersuchung eines Silylons. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201308609] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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38
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Soriano E, Fernández I. Allenes and computational chemistry: from bonding situations to reaction mechanisms. Chem Soc Rev 2014; 43:3041-105. [DOI: 10.1039/c3cs60457h] [Citation(s) in RCA: 140] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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39
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Design and synthesis of guanylthiourea derivatives as potential inhibitors of Plasmodium falciparum dihydrofolate reductase enzyme. Bioorg Med Chem Lett 2014; 24:613-7. [DOI: 10.1016/j.bmcl.2013.12.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 11/22/2013] [Accepted: 12/02/2013] [Indexed: 11/18/2022]
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40
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Ruiz DA, Melaimi M, Bertrand G. Carbodicarbenes, Carbon(0) Derivatives, Can Dimerize. Chem Asian J 2013; 8:2940-2. [DOI: 10.1002/asia.201300887] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Revised: 07/18/2013] [Indexed: 11/10/2022]
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41
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Broeckaert L, Frenking G, Geerlings P, De Proft F. Reactivity of Dicoordinated Stannylones (Sn
0
) versus Stannylenes (Sn
II
): An Investigation Using DFT‐Based Reactivity Indices. Chemphyschem 2013; 14:3233-47. [DOI: 10.1002/cphc.201300596] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Lies Broeckaert
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels (Belgium)
| | - Gernot Frenking
- Fachbereich Chemie, Philipps‐Universität Marburg, Hans‐Meerwein‐Straße, 35032 Marburg (Germany)
| | - Paul Geerlings
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels (Belgium)
| | - Frank De Proft
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels (Belgium)
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42
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Push–pull allenes-conjugation, (anti)aromaticity and quantification of the push–pull character. Tetrahedron 2013. [DOI: 10.1016/j.tet.2013.01.027] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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43
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Kasetti Y, Bharatam PV. Pharmacophoric features of drugs with guanylurea moiety: an electronic structure analysis. J Mol Model 2013; 19:1865-74. [DOI: 10.1007/s00894-012-1743-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Accepted: 12/17/2012] [Indexed: 11/29/2022]
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44
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Dhaked DK, Bharatam PV. Nitro ⇌ aci-nitro tautomerism and E/Z isomeric preferences of nitroethenediamine derivatives: a quantum chemical study. RSC Adv 2013. [DOI: 10.1039/c3ra43621g] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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45
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Bhatia S, Bagul C, Kasetti Y, Patel DS, Bharatam PV. Divalent N(I) character in 2-(thiazol-2-yl)guanidine: an electronic structure analysis. J Phys Chem A 2012; 116:9071-9. [PMID: 22920939 DOI: 10.1021/jp304789u] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Several medicinally important compounds carry a 2-(thiazol-2-yl)guanidine unit. These species are generally (erroneously) represented as 1-(thiazol-2-yl)guanidine species. Quantum chemical studies were performed to identify the appropriate tautomeric state of this class of compounds. B3LYP/6-31+G(d) calculations indicate the preferred tautomeric state of these species is associated with the 2-(thiazol-2-yl)guanidine structure rather than the 1-(thiazol-2-yl)guanidine structure. G2MP2 calculations on the model system were carried out to study the electronic structure, electron delocalization, and protonation energy; MESP, ELF, HOMA, AIM, and NBO analyses were also carried out. The results indicate that this class of compounds may be treated as species with hidden ::N(←L)R character. Upon protonation of the thiazole ring nitrogen, these systems show the electronic structure as in ::N(←L)2(⊕) systems with divalent N(I) oxidation state.
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Affiliation(s)
- Sonam Bhatia
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER) , Sector 67, S. A. S. Nagar, Punjab 160062, India
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46
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Effect of substituents at the heteroatom on the structure and ligating properties of carbodicarbenes and its silicon analogs: a theoretical study. Theor Chem Acc 2012. [DOI: 10.1007/s00214-012-1134-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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47
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Patel DS, Bharatam PV. Divalent N(I) compounds with two lone pairs on nitrogen. J Phys Chem A 2011; 115:7645-55. [PMID: 21650162 DOI: 10.1021/jp111017u] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Carbon with the C(0) state has been reported recently, examples of which were known for the past decades. Silicon in the Si(0) state and phosphorus in the P(I) state are also known experimentally. This prompted us to search for divalent N(I) compounds, which resulted in the identification of ::N(←L)(2)(⊕) systems with bicoordinated nitrogen in the N(I) formal oxidation state. It was found that several biguanide derivatives (especially in their protonated state) belong to this class. Quantum chemical analysis provided the structural details, molecular orbitals, charge localization (vs delocalization) trends, etc. This class of compounds has been found to be characterized by two lone pairs on the central nitrogen, very similar to the central carbon in divalent C(0) compounds (::C(←L)(2)). The new bonding environment for nitrogen reported in this article, divalent nitrogen N(I), is clearly different from the nitrenium ions NR(2)(⊕). The electronic structure and reactivity of representative examples of this novel class of divalent nitrogen N(I) systems (::N(←L)(2)(⊕)) have been analyzed in detail, in terms of molecular orbitals, atomic charges, protonation energies, complexation energies with Lewis acids like BH(3), AlCl(3), and AuCl and compared with those of divalent C(0) systems.
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Affiliation(s)
- Dhilon S Patel
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Sector 67, S. A. S. Nagar (Mohali), Punjab 160 062, India
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