PRODUCTION OF OPTICALLY ACTIVE TRANS-CYCLOBUTANEDICARBOXYLIC ACIDS

摘要

PROBLEM TO BE SOLVED: To obtain the subject compound by reacting racemic-trans- cyclobutanedicarboxylic acids with an optically active amine to deposit either one diastereomeric salt and subjecting the salt to acid decomposition to directly optically resolve the racemic trans-cyclobutanedicarboxylic acids. SOLUTION: A racemic trans-cyclobutanedicarboxylic acid of formula I (R is a lower alkyl) is reacted with an optically active amine to preferentially deposit either one of diastereomer salt and the salt is decomposed with an acid to provide the objective compound of formula II or III. An optically active phenylethylamine derivative of formula IV (* is an asymmetric carbon atom; R<1> is hydrogen or benzyl; R<2> is hydrogen or phenyl; R<3> is hydrogen or methyl) is preferable as the optically active amine. The optically active amine is preferably used in an amount of 0.38-0.8 mol based on l mol compound of formula I. The reaction of the compound of formula I with the optically active amine is preferably carried out in an organic solvent, at >=0 deg.C and a temperature lower by 20 deg.C than boiling point of the solvent.