Mechanism of the palladium-catalyzed hydrothiolation of alkynes to thioethers: a DFT study.

The mechanisms of the palladium-catalyzed hydrothiolation of alkynes with thiols were investigated using density functional theory at the B3LYP/6-31G(d, p) (SDD for Pd) level. Solvent effects on these reactions were explored using the polarizable continuum model (PCM) for the solvent tetrahydrofuran (THF). Markovnikov-type vinyl sulfides or cis-configured anti-Markovnikov-type products were formed by three possible pathways.

On-line conversion and determination of artemisinin using a flow-injection capillary electrophoresis system.

A novel, rapid, and simple capillary electrophoresis (CE) method has been developed for the determination of antimalarial artemisinin by on-line treatment with alkaline. By on-line reaction, artemisinin was automatically and reproducibly converted to the strongly UV-absorbing compound, Q292, by treating it with 0.20 mol/L NaOH solution for 3 min at 40 degrees C.