OPTICALLY ACTIVE COMPOUND AND ITS PRODUCTION

摘要

NEW MATERIAL:The optically active compound of formula I [R<1> is 1-12C group selected from (alkoxy)alkyl, cycloalkyl and aralkyl having hetero atom on aromatic ring or alkyl; R<2> is H or easily eliminable protecting group selected from acyl, silyl, aralkyl and alkyloxyalkyl; R<4> is 1-5C lower alkyl; * represents asymmetric carbon atom]. EXAMPLE:The compound of formula II. USE:Useful as a production raw material for optically active gamma-lactone derivative which is a key intermediate for the synthesis of prostaglandin. PREPARATION:The objective compound of formula I can be produced by reacting a compound of formula III with a trialkyl orthoacetate of formula IV (R<4> is 1-5C lower alkyl) in the presence of an acid catalyst under heating. The starting compound of formula III can be synthesized from a compound of formula V via several steps.