Novel C 2-symmetric chiral ligands: enantioselective transformation of cyclic 1,2-diols into 1,2-bis(phenylsulfenyl) and 1,2-bis(phenylselenyl) derivatives

Abstract: Chiral C 2-symmetric S,S- and Se,Se-donating ligands as well as the C 1 mixed S,Se-donating ligands were prepared from optically active 1,2-cyclohexanediol and 1,2-cyclopentanediol via the respective SN2 reactions. The bis(chalcogen) ligands obtained effectively catalyze the asymmetric allylic alkylation with enantioselectivities of up to 50% ee. [Copyright &y& Elsevier]