Sterically hindered chiral (salen)manganese complexes bearing
long perfluoroalkyl substituents are synthesized and successfully employed
as catalysts in the enantioselective (ee = 50–87%) epoxidation of
alkenes under fluorous biphasic conditions.
provide ees higher than those attainable with first generation fluorous chiral (salen)manganese complexes featuring perfluoroalkyl substituents in the key positions (3,3′ and 5,5′) in the ligand. Second generation catalysts (Mn-6)C7F15COO and (Mn-7)C7F15COO were successfully employed in the fluorous biphase epoxidation of alkenes with PhIO as the oxidant and pyridine N-oxide as an additive. Epoxide yields