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Theoretical Study on Epoxide Ring-opening in CO2/Epoxide Copolymerization Catalyzed by Bifunctional Salen-Type Cobalt(III) Complexes: Influence of Stereoelectronic Factors. Catalysts 2021. [DOI: 10.3390/catal11030328] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Propylene oxide (PO) binding and ring-opening reaction with the bifunctional CO2/epoxide copolymerization catalyst, based on the Co(III)-salcy complex including two quaternary ammonium salts with n-butyl substituents (N+-chains) were investigated by Density Functional Theory (DFT) calculations and compared with the model systems without the N+-chains. The importance of the different possible stereoisomers and the stereoselectivity of these processes for (S)- and (R)-enantiomers of PO were considered. To explore the conformational space for the real catalyst, a complex approach, developed previously was applied. The calculations for the model systems directly demonstrate that PO-ring opening proceeds preferentially in trans catalysts’ configuration and no participation of cis-β isomers is viable; nucleophilic attack at the methylene-carbon atom is preferred over that at methine-carbon atom. For the real bifunctional catalyst, with the (S,S)-configuration of cyclohexane, the results indicate a preference of (R)-PO ring-opening over (S)-PO ring-opening (ca. 6:5). Concerning stereoisomers resulting from the orientation of N+-chains in the real catalyst, different groups of structures participate in the ring-opening reaction for (R)-PO, and different for (S)-PO. The high population of nonreactive complexes of (R)-PO may be the key factor responsible for decreasing the activity of the analyzed catalyst in the epoxide ring-opening reaction.
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Khalaji AD, Hadadzadeh H, Fejfarova K, Dusek M. Metal-dependent assembly of a tetranuclear copper(II) complex versus a 1D chain coordination polymer of cobalt(III) complex with N2O2-chelating Schiff-base ligand: Synthesis, characterization and crystal structures. Polyhedron 2010. [DOI: 10.1016/j.poly.2009.11.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Dehno Khalaji A, Weil M, Hadadzadeh H, Daryanavard M. Two different 1D-chains in the structures of the copper(I) coordination polymers based on bidentate Schiff-base building units and thiocyanate anions as bridging ligands. Inorganica Chim Acta 2009. [DOI: 10.1016/j.ica.2009.06.033] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Khalaji AD, Amirnasr M, Triki S. New coordination polymer based on salpn Schiff base and azide bridging ligands: Synthesis and structural characterization of {Na[CoIII(μ-salpn)(μ1,1-N3)2]}n (H2salpn=N,N′-bis(salicylidene)-1,3-diaminopropane). Inorganica Chim Acta 2009. [DOI: 10.1016/j.ica.2008.03.111] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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