Synthesis of alkenyl sulfides catalyzed by CuNPs/TiO2. A theoretical-computational analysis

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

Santiago de Compostela

Congreso; The 24th International Electronic Conference on Synthetic Organic Chemistry; 2020

Alkenyl sulfides are recognised constituents of the sulphur containing organic compounds and they are of great interest because they can be used as versatile building blocks in organic synthesis. The alkyne hydrothiolation, is a simple approach to produce alkenyl sulfides from thiols and alkynes. In principle can lead to one of the regio- and stereoisomeric alkenyl sulfides through a Markovnikov orientation, E linear and Z linear, or give mixtures of them through an anti-Markovnikov orientation. Regarding thiols, in our research group, it has been reported a systematic and straightforward procedure for the synthesis of thiols with potential applications in materials chemistry. On the other hand, in the last years, we have been working in the development of methodologies based on the use of supported copper nanocatalysts, and the copper-based catalytic systems could activate both the alkyne and the thiol in this reaction. On this basis, we report our results about the theoretical study of hydrothiolation reaction between different alkynes and thiols derivatives catalysed by CuNPs supported on TiO2 (CuNPs/TiO2) in dichloromethane (DCM). Activated alkynes bearing an adjacent electron-withdrawing group gave conversions from good to excellent of anti-Markovnikov Z-alkenyl sulfides, while the unactivated alkynes did not react. To explain this, a theoretical study was carried out with different DFT methods for deriving partial atomic charges for all the alkynes. Furthermore, since we assumed that the reaction starts when the alkyne is activated by the copper, we computationally modelled the active copper nanocatalyst structure.