[EN] CATALYTIC COMPOSITIONS AND METHODS FOR ASYMMETRIC ALLYLIC ALKYLATION<br/>[FR] COMPOSITIONS ET PROCEDES CATALYTIQUES D'ALKYLATION ALLYLIQUE ASYMETRIQUE
申请人:THE BOARD OF TRUSTEES OF THE LELAND STANFORD JUNIOR UNIVERSITY
公开号:WO1999032225A2
公开(公告)日:1999-07-01
(EN) Complexes of a selected class of chiral ligands with molybdenum, tungsten or chromium, preferably molybdenum, are effective as catalysts in highly enantioselective and regioselective alkylation of allylic substrates. Such compositions provide a versatile and low-cost alternative to existing catalysts. The chiral ligand comprises: (i) a chiral component having first and second chiral centres each substituted with a group X selected from -O- and -NR-, where R is hydrogen or lower alkyl, and (ii) linked to each said group X, a binding group CyN comprising a heterocyclic group having a ring nitrogen atom and optionally substituted with one or more groups selected from alkyl, alkenyl, aryl, aralkyl, alkoxy, aryloxy, acyl, acyloxy, amide, tertiary amine, nitro and halogen, and optionally fused to one or more additional rings.(FR) Des complexes d'une classe sélectionnée de ligands chiraux avec du molybdène, du tungstène ou du chrome, de préférence du molybdène, sont efficaces en tant que catalyseurs dans l'alkylation hautement éniantosélective et régiosélective de substrats allyliques. Ces compositions offrent une alternative polyvalente et bon marché aux catalyseurs existants.