Enantioselective catalysis; 130: Optically active expanded ligands based on the trans-1,2-substituted cyclopentane skeleton

New expanded bisphosphane ligands with a chiral trans-1,2-substituted cyclo pentane skeleton were prepared. Polyaldehydes were accessible by coupling o ptically active bisphosphane precursors with branched aryl bromides. Optica lly active expanded ligands were obtained by condensation of the aldehydes with chiral amines and amino alcohols. The optically active ligands were te sted in several model reactions of enantioselective catalysis, including al lylic alkylation, hydrogenation (adopted to the use of water), and hydrosil ylation.