To produce the subject compound on an industrial scale by reacting a 1-alkoxycarbonyl-2-hydroxymethylcyclopropane-1-carboxylic acid with an optically active N-benzyl-α-phenylethylamine.
The objective optically active compound is produced by incorporating a racemic 3-oxa-2-oxobicyclo[3.1.0]hexane-1-carboxylic acid ester with equivalent amount of a base to obtain a salt of a 1-alkoxycarbonyl-2- hydroxymethylcyclopropane-1-carboxylic acid of formula I [R is an (aryl- substituted)1-10C alkyl], reacting the salt with an optically active N-benzyl-α- phenylethylamine (a resolution agent), crystallizing in the form of a 1- alkoxycarbonyl-2-hydroxymethylcyclopropane-1-carboxylic acid N-benzyl-α- phenylethylamine diastereomer salt of formula II (* is an asymmetric carbon atom), separating as an optically active compound of the formula I with a base, removing the resolution agent and acidifying the product.
TSUJI HISASHI
KATAOKA NORIYASU
YATAGAI MASANORI
