| 摘要 |
A compound of formula (Ia) or (Ib), wherein A and B each independently represents hydrogen or one, two or three naphthylidene substituents, which substituents are selected from C1-6 alkyl, C1-6 alkoxy, aryl, aryloxy, silyl and silyloxy; R1 represents phenyl, C1-6 alkyl, phenyl C1-6 alkyl or a moiety of formula (a): wherein R2 represents C1-6 alkyl, phenyl or benzyl, R3 represents H or OR4 wherein R4 is C1-6 alkyl or C1-6 alkylsilyl and n is zero or an integer 1 or 2; and X is a counter ion; a process for the preparation of such compounds and the use of such compounds for enantioselectively epoxidising a prochiral olefin.
|
