Patent ID: 7795478
Filing Date: 2010-09-14
Classification: C07B,C07C

Abstract:
1. A process for producing an optically active, fluorine-containing, benzyl alcohol represented by formula [5] wherein m is 0, 1, 2, 3, 4 or 5 and represents the number of fluorine atom substituents, n is 0, 1, 2 or 3 and represents the number of trifluoromethyl group substituents, m and n are not both 0 and the total of m and n is 5 or less, R represents an alkyl group with 1-6 carbon atoms, and * represents that the benzyl alcohol is an optically active molecule, comprising the steps of: (a) reacting a fluorine-containing benzaldehyde represented by formula [1] wherein m and n are defined as above, with an alkyl Grignard reagent represented by formula [2] wherein R is defined as above, and X represents a halogen atom selected from chlorine, bromine and iodine], to convert the benzaldehyde to a magnesium alkoxide of racemic, fluorine-containing, benzyl alcohol represented by formula [3] wherein m, n, R and X are the same as above, and the wavy line represents that it the magnesium alkoxide is a racemate; (b) reacting the magnesium alkoxide with phthalic anhydride to obtain a phthalate half ester of racemic, fluorine-containing, benzyl alcohol represented by formula [4] wherein m, n, R and the wavy line are the same as above; (c) optically resolving the half ester by optically active 1-phenylethylamine, and (d) hydrolyzing the ester group of the half ester obtained in step (c), thereby obtaining the optically active fluorine-containing benzyl alcohol.