Patent ID: 7371578

Claim:
A method of evaluating the catalytic activity of a rare earth alkoxide, comprising the steps of: preparing a rare earth alkoxide solution by dissolving a rare earth alkoxide represented by Ln(OR) 3 in THF having a water content of 20 ppm or less wherein Ln represents a rare earth and R represents a C 1 to C 5 alkyl group heat treating the rare earth alkoxide solution for 1 to 3 hours at 35° C. to 60° C., adding the heat treated rare earth alkoxide solution to optically active 2,2′ -dihydroxy-1,1′-binaphthol (BINOL) represented by formulae 1 or 2: to prepare a rare earth complex catalyst, and using the rare earth complex catalyst to conduct the asymmetric epoxidation, of an enone represented by formula 3: wherein R 1 , R 2 , R 3 and R 4 independently represent a hydrogen atom or a C 1-10 alkyl group, an aromatic group and an imidazolyl group, each of which may be substituted with a halogen atom, a C 1-10 alkyl group, an aromatic group, and an aromatic group which may be substituted with 1 to 3 halogen atoms, whereby the amount of an epoxy enone formed in the asymmetric epoxidation, the amount of the unreacted enone, and enantiomeric excess of the epoxy enone may be measured.