Kinetic Resolution of Thiols

Significance

An efficient direct acylative kinetic resolution of racemic secondary thiols 1 was reported by the authors, using a novel sulfonamide catalyst derived from a cinchona alkaloid. Under optimal conditions (10 mol% catalyst loading, ;-30 ˚C in MTBE), with 2 as the electrophile, various secondary aromatic thiols can be resolved with high er at ˜50% conversion. The selectivity (S = k _fast/k _slow) of the resolution is in the range of 50-275. In addition, during the kinetic resolution of the thiols, a simultaneous desymmetrization of a meso-anhydride electrophile (like 2) also occurred with excellent enantioselectivity.