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Mandal C, Joshi S, Mishra S, Mukherjee D. Heteroleptic Magnesium n-Butyl on a Chemically Non-innocent 2-Anilidomethylpyridine Ligand Leading to Diverse Magnesium Hydrides. Inorg Chem 2024; 63:15692-15704. [PMID: 39110541 DOI: 10.1021/acs.inorgchem.4c01612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/27/2024]
Abstract
Molecular magnesium hydrides and hydride-rich clusters are of significant interest for applications ranging from catalysis and small molecule activation to hydrogen storage. Here, we investigate the 2-anilidomethylpyridine framework NNL as an ancillary support for magnesium organometallics with a special emphasis on hydrides. The proligand NNLH (N-[2,6-bis(1-methylethyl)phenyl]-α,6-diphenyl-2-pyridinemethanamine) gives [(NNL)Mg(nBu)(thf)] (1) by nbutane elimination from Mg(nBu)2(thf)n. A stronger donor such as DMAP replaces the THF from 1 to give [(NNL)Mg(nBu)(dmap)] (2). Both are air-sensitive, and 1 is adventitiously oxidized into [(NNL)Mg(μ-OnBu)]2 (32). The homoleptic [(NNL)2Mg] (8) is made from 1 and a second equiv of NNLH. 1's terminal nBu group is selectively protonated by HN(SiMe3)2 to give [(NNL)MgHMDS] (4; HMDS = N(SiMe3)2), whereas Ph3SiOH partially protonates the backbone anilide as well to give a mixture of [(NNL)Mg(OSiPh3)(thf)] (5) and free NNLH. Like HN(SiMe3)2, aprotic MeOTf also reacts by selectively abstracting the nBu group from 1 to give [(NNL)Mg(μ:κ2-O,O'-OTf)(thf)]2 (62). Interestingly, screening the common synthetic routes for magnesium hydrides leads to diverse outcomes upon varying the Mg precursors and hydride sources. 1 and PhSiH3 give the hydride cluster [{(NNL)2Mg2(μ-H)}2(μ-H)4Mg] (7), whereas 2 and PhSiH3 give the molecular complex [(NNLde)Mg(dmap)2] (9) with a dearomatized pyridyl backbone. 1 and HBpin (pinacolborane) give a product mixture, from which a different hydride cluster [(NNL)2Mg2(μ-H)}2(μ:κ2-O,O'-O2C2Me4)] (10) is identified, showing a rare instance of complete deborylation of a HBpin molecule. 1 and HBcat (catecholborane) also give a product mixture, one of which is the borylated ligand [(NNL)Bcat] (11). HBpin with 4 as the Mg precursor takes the ligand borylation route more selectively to give [(NNL)Bpin] (12). Last, 1 reacts with iPrNH2BH3 to give [(NNL)Mg{NH(iPr)BH3}] (13), which shows a slow and fractional conversion into the dinuclear mixed hydrido amidoborane [(NNL)2Mg2(μ-H){(μ-NH(iPr)BH3}] (14) by partial β-hydride elimination. In comparison, [(NNL)Mg(iPrNHBH3)(dmap)] (15) arising from the DMAP-bound 2 and iPrNH2BH3 is stable toward such elimination.
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Affiliation(s)
- Chhotan Mandal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India
| | - Shalini Joshi
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India
| | - Sabyashachi Mishra
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India
| | - Debabrata Mukherjee
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India
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Mandal C, Joshi S, Das S, Mishra S, Mukherjee D. 2-Anilidomethylpyridine-Derived Three-Coordinate Zinc Hydride: The Journey Unveils Anilide Backbone's Reactive Nature. Inorg Chem 2024; 63:739-751. [PMID: 38127496 DOI: 10.1021/acs.inorgchem.3c03673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
Low-coordinate heteroleptic zinc hydrides are catalytically important but rare and synthetically challenging. We herein report three-coordinate monomeric zinc hydride on a 2-anilidomethylpyridine framework (NNL). The synthetic success comes through systematically screening a few different routes from different precursors. During the process, the ligand's anilide backbone interestingly appears to be more reactive than Zn's terminal site to electrophilic Lewis and Brønsted acids. The proligand NNLH reacts with [Zn{N(SiMe3)2}2] and ZnEt2 to give [(NNL)ZnA] (A = N(SiMe3)2 (1), Et(2)). Both are inert to PhSiH3 and H2 but react with HBpin only through the internal Zn-Nanilide bond to give the borylated ligand NNLBpin (3). The reactions of 1 and 2 with Ph3EOH (E = C, Si) afford a series of divergent compounds like [(NNLH)Zn(OSiPh3)2] (4), [Zn3(OSiPh3)4Et2] (5), and [EtZn(OCPh3)] (6). But in all cases, it is invariably the Zn-Nanilide bond protonated by the -OH with equal or higher preference than the terminal Zn-N or Zn-C bonds. A DFT analysis rationalizes the origin of such a reactivity pattern. Realizing that an acid-free route might be the key, reacting [(NNL)Li] with ZnBr2 gives [(NNL)Zn(μ-Br)]2 (7), which on successively treating with KOSiPh3 and PhSiH3 gives the desired [(NNL)ZnH] (8) as a three-coordinate monomer with a terminal Zn-H bond. Estimating the ligand steric in 8 shows the openness in Zn's coordination sphere, a desired criterion for efficient catalysis. This and a positive influence of the pyridyl sidearm is reflected in 8's superior activity in hydroborating PhC(O)Me by HBpin in comparison to Jones' two-coordinate anilido zinc hydride.
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Affiliation(s)
- Chhotan Mandal
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, West Bengal, India
| | - Shalini Joshi
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
| | - Sanjay Das
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, West Bengal, India
| | - Sabyashachi Mishra
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
| | - Debabrata Mukherjee
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, West Bengal, India
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Jiang Y, Zhang W, Han M, Wang X, Solan GA, Wang R, Ma Y, Sun WH. Phenoxy-imine/-amide aluminum complexes with pendant or coordinated pyridine moieties: Solvent effects on structural type and catalytic capability for the ROP of cyclic esters. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.124602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Kosuru SR, Lai FJ, Chang YL, Li CY, Lai YC, Ding S, Wu KH, Chen HY, Lo YH. Collaboration between Trinuclear Aluminum Complexes Bearing Bipyrazoles in the Ring-Opening Polymerization of ε-Caprolactone. Inorg Chem 2021; 60:10535-10549. [PMID: 34232620 DOI: 10.1021/acs.inorgchem.1c01192] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Trinuclear aluminum complexes bearing bipyrazoles were synthesized, and their catalytic activity for ε-caprolactone (CL) polymerization was investigated. DBu2Al3Me5 exhibited higher catalytic activity than did the dinuclear aluminum complex LBu2Al2Me4 (16 times as high for CL polymerization; [CL]:[DBu2Al3Me5]:[BnOH] = 100:0.5:5, [DBu2Al3Me5] = 10 mM, conversion 93% after 18 min at room temperature). Density functional theory calculations revealed a polymerization mechanism in which CL first approached the central Al atom and then moved to an external Al. The coordinated CL ring was opened because the repulsion of two tert-butyl groups on the ligands pushed an alkoxide initiator on an external Al to initiate CL. In these trinuclear Al catalysts, the central Al plays a role in monomer capture and then collaborates with the external Al to activate CL, accelerating polymerization.
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Affiliation(s)
- Someswara Rao Kosuru
- Department of Medicinal and Applied Chemistry, Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan, Republic of China
| | - Feng-Jie Lai
- Department of Dermatology, Chi Mei Medical Center, Tainan, Taiwan, Republic of China.,Center for General Education, Southern Taiwan University of Science and Technology, Tainan, Taiwan, Republic of China
| | - Yu-Lun Chang
- Department of Medicinal and Applied Chemistry, Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan, Republic of China
| | - Chen-Yu Li
- Department of Medicinal and Applied Chemistry, Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan, Republic of China
| | - Yi-Chun Lai
- Department of Medicinal and Applied Chemistry, Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan, Republic of China
| | - Shangwu Ding
- Department of Medicinal and Applied Chemistry, Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan, Republic of China.,Department of Chemistry, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan, Republic of China
| | - Kuo-Hui Wu
- Department of Chemistry, National Central University, Taoyuan 32001, Taiwan, Republic of China
| | - Hsuan-Ying Chen
- Department of Medicinal and Applied Chemistry, Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan, Republic of China.,Department of Chemistry, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan, Republic of China.,Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan, Republic of China
| | - Yung-Han Lo
- Department of Chemistry, Faculty of Science and Technology, Keio University, Minato City 108-8345, Tokyo, Japan
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Novák M, Jambor R, Růžičková Z, Podzimek Š. Unique reactivity of an α-ketiminopyridine ligand with metal–alkyls: Synthesis and ROP of ε-caprolactone. NEW J CHEM 2021. [DOI: 10.1039/d0nj05498d] [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
The reaction of an α-ketimininopyridine ligand 2-((Me)CN(C6H3-2,6-iPr2))-6-(OMe)C5H3N (L1) with metal–alkyls, such as MeLi, Et2Zn, Me3Al and Me2AlCl, was studied.
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Affiliation(s)
- Miroslav Novák
- Institute of Chemistry and Technology of Macromolecular Materials
- Faculty of Chemical Technology
- University of Pardubice
- 53210 Pardubice
- Czech Republic
| | - Roman Jambor
- Department of General and Inorganic Chemistry
- Faculty of Chemical Technology
- University of Pardubice
- 53210 Pardubice
- Czech Republic
| | - Zdeňka Růžičková
- Department of General and Inorganic Chemistry
- Faculty of Chemical Technology
- University of Pardubice
- 53210 Pardubice
- Czech Republic
| | - Štěpán Podzimek
- Institute of Chemistry and Technology of Macromolecular Materials
- Faculty of Chemical Technology
- University of Pardubice
- 53210 Pardubice
- Czech Republic
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Use of Metal Catalysts Bearing Schiff Base Macrocycles for the Ring Opening Polymerization (ROP) of Cyclic Esters. Catalysts 2017. [DOI: 10.3390/catal7050165] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Al-Najjar N, Solan GA, Singh K. Crystal structure of (aceto-nitrile-κ N)iodido-(2-(naphthalen-1-yl)-6-{1-[(2,4,6-tri-methyl-phen-yl)imino]ethyl}-pyridine-κ 2N, N')copper(I). ACTA CRYSTALLOGRAPHICA SECTION E-CRYSTALLOGRAPHIC COMMUNICATIONS 2016; 72:1845-1847. [PMID: 27980846 PMCID: PMC5137624 DOI: 10.1107/s2056989016018685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 11/22/2016] [Indexed: 11/21/2022]
Abstract
The CuI atom in the molecular structure of the title compound exhibits a distorted tetrahedral coordination sphere, defined by two N atoms of the chelating ligand, one N atom of the acetonitrile ligand and one iodide ligand. In the mononuclear title complex, [CuI(C2H3N)(C26H24N2)], the CuI ion has a distorted tetrahedral coordination environment, defined by two N atoms of the chelating 2-(naphthalen-1-yl)-6-[(2,4,6-trimethylphenyl)imino]pyridine ligand, one N atom of an acetonitrile ligand and one iodide ligand. Within the complex, there are weak intramolecular C—H⋯N hydrogen bonds, while weak intermolecular C—H⋯I interactions between complex molecules, help to facilitate a three-dimensional network.
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Affiliation(s)
- Nada Al-Najjar
- Department of Chemistry, College of Science for Women, University of Baghdad, Iraq
| | - Gregory A Solan
- Department of Chemistry, University of Leicester, University Road, Leicester LE1 7RH, England
| | - Kuldip Singh
- Department of Chemistry, University of Leicester, University Road, Leicester LE1 7RH, England
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Molecular Catalysis for Precise Olefin Polymerization and ROP 2015. Catalysts 2016. [DOI: 10.3390/catal6040053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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9
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Huang YT, Wang WC, Hsu CP, Lu WY, Chuang WJ, Chiang MY, Lai YC, Chen HY. The ring-opening polymerization of ε-caprolactone and l-lactide using aluminum complexes bearing benzothiazole ligands as catalysts. Polym Chem 2016. [DOI: 10.1039/c6py00569a] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of aluminum complexes bearing benzothiazole ligands was synthesized and the ring-opening polymerization of ε-caprolactone (CL) and l-lactide (LA) using these aluminum complexes as catalysts was studied.
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Affiliation(s)
- Yen-Tzu Huang
- Department of Medicinal and Applied Chemistry
- Kaohsiung Medical University
- Kaohsiung
- Republic of China
| | - Wei-Chu Wang
- Department of Medicinal and Applied Chemistry
- Kaohsiung Medical University
- Kaohsiung
- Republic of China
| | - Chun-Pin Hsu
- Department of Medicinal and Applied Chemistry
- Kaohsiung Medical University
- Kaohsiung
- Republic of China
| | - Wei-Yi Lu
- Department of Medicinal and Applied Chemistry
- Kaohsiung Medical University
- Kaohsiung
- Republic of China
| | - Wan-Jung Chuang
- Department of Medicinal and Applied Chemistry
- Kaohsiung Medical University
- Kaohsiung
- Republic of China
| | - Michael Y. Chiang
- Department of Medicinal and Applied Chemistry
- Kaohsiung Medical University
- Kaohsiung
- Republic of China
- Department of Chemistry
| | - Yi-Chun Lai
- Department of Medicinal and Applied Chemistry
- Kaohsiung Medical University
- Kaohsiung
- Republic of China
| | - Hsuan-Ying Chen
- Department of Medicinal and Applied Chemistry
- Kaohsiung Medical University
- Kaohsiung
- Republic of China
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