Synthesis of Optically Active Organoantimony Compounds Having an (S)-α-Methylbenzyldimethylamine Group and Its Evaluation for Asymmetric Reaction

Abstract

Novel, enantiomerically pure organoantimony compounds having a C-chiral amine moiety, (S)-(α-methyl-2-di-p-tolylstibanobenzyl)dimethylamine [AMSb] (2) and its (η⁶-arene)chromium complex [AMSb–Cr(CO)₃] (4), were prepared from common (S)-(α-methylbenzyl)dimethylamine (1) via its ortho-lithiated intermediates in short steps. The catalytic activity and enantioselectivity of the ligands 2 and 4 for asymmetric reaction are evaluated, and the optically active (η⁶-arene)chromium complex 4 has been shown to be an effective ligand for rhodium-catalyzed asymmetric hydrosilylation of ketones.