Enantioselective Epoxidation of Conjugatedtrans-Olefins with (Salen)manganese(III) Complexes as Catalysts

Epoxidation of trans-β-substituted styrene derivatives was examined with (salen)manganese(III) complexes as catalysts. (R,R)-(Salen)manganese(III) complex 3 was found to be a better catalyst for epoxidation of substrates bearing an alkyl substituent at their β-carbon, while (R,S)-(salen)manganese(III) complex (2 or 4) was a better catalyst for epoxidation of substrates bearing an unsaturated substituent at their β-carbon.