A quaternary ammonium salt represented by formula (5)(wherein R1 represents an alkyl group having 1 to 4 carbon atoms, R2 represents an alkyl group having 1 to 10 carbon atoms, R3 represents an alkyl group having 1 to 10 carbon atoms that is optionally substituted with one or more phenyl groups or a phenyl group that optionally has one or more groups selected from the group consisting of alkyl groups having 1 to 10 carbon atoms and a trifluoromethyl group, R4 represents an alkyl group having 1 to 4 carbon atoms, R5 represents an alkyl group having 1 to 10 carbon atoms, C* represents an asymmetric carbon atom, and X− represents a halide ion) can be used as a catalyst having good stability under basic conditions.
