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Hydrothiolation of alkynes with thiol–catechol derivatives catalysed by CuNPs/TiO2: exploring the reaction mechanism by DFT calculations† † Electronic supplementary information (ESI) available: Computational procedure, xyz coordinates and total energies in atomic units for all of the calculated structures. See DOI: https://doi.org/10.1039/d3ra00169e

ABSTRACT: Density functional theory (DFT) calculations were applied to describe the hydrothiolation reaction of activated alkynes with thiols bearing a catechol group. The thiol-yne click (TYC) process was efficiently catalysed by a CuNPs/TiO2 nanocatalyst giving the corresponding anti-Markovnikov vinyl sulphides with high Z-stereoselectivity. Based on the experimental results and DFT studies, a plausible reaction mechanism is proposed, which implies the activation of the carbon–carbon triple bond by coordination to the copper centre, followed by a stereoselective (external) nucleophilic attack to give preferentially the Z-vinyl sulphide isomer. Additionally, experimental and theoretical studies strongly correlate with the proposed synergistic role for the TiO2 support in the catalytic process. Based on experimental results and DFT studies, a detailed reaction mechanism is presented for the CuNPs/TiO2-catalysed hydrothiolation of activated alkynes with thiols bearing a catechol group.

SUBMITTER: Capurso M

PROVIDER: S-EPMC9999702 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature

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