Computational study on atom-economic alkyne hydrotelluration reaction using benchmarked ECP for Te.

Geometry and energy calibration studies are done for arriving at a proper ECP for tellurium containing compounds. Among the various d-function included ECPs cc-pwCVTZ-PP and def2-TZVP give more reliable results. Non-catalytic and base/radical initiated hydrotelluration reactions are computationally studied using the calibrated def2-TZVP, with a special focus on the regio-and stereoselective formation of vinyl tellurides. The explored gas phase reaction mechanism indicates the addition of tellurol to unsaturated carbon-carbon triple bond via a concerted transition structure. Regioselectivity has been noticeably realized in presence of both base and radical mediated hydrotelluration leading to Markovnikov and anti-Markovnikov product respectively.