Hydrothiolation of alkynes with thiol–catechol derivatives catalysed by CuNPs/TiO 2 : exploring the reaction mechanism by DFT calculations

CAPURSO, MATÍAS; RADIVOY, GABRIEL; NADOR, FABIANA; DORN, VIVIANA

RSC Advances

Royal Society of Chemistry

Año: 2023 vol. 13 p. 8025 - 8033

Density functional theory (DFT) calculations were applied to describe the hydrothiolation reaction ofactivated 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.