Patent ID: RE39333

Claim:
A process for producing a 5-hydroxy-3-oxopentanoic acid derivative of the following formula (IV): wherein R 1 represents any of an alkyl group of 1 to 12 carbon atoms, an aryl group of 6 to 12 carbon atoms and an aralkyl group of 7 to 1:2 carbon atoms; and R 2 represents any of hydrogen, an alky, group of 1 to 12 carbon atoms which may have a substituent, an alkenyl group of 2 to 12 carbon atoms which may have a substituent, an aryl group of 6 to 12 carbon atoms which may have a substituent, an aralkyl group of 7 to 12 carbon atoms which may have a substituent, a cyano group, a carboxy group and an alkoxycarbonyl group, which comprises permitting adding a lithium amide of the following formula (III): wherein R 4 and R 5 may be the same or different and each represents any of an alkyl group of 1 to 12 carbon atoms, an aryl group of 6 to 12 carbon atoms, an aralkyl group of 7 to 12 carbon atoms and a silyl group, to act upon a mixture of an acetic acid ester of the following formula (I) and a 3-hydroxypropionic acid derivative of the following formula (II) at a temperature not below −20° C. to conduct reaction : CH 3 CO 2 R 1 (I) wherein R 1 represents any of an alkyl group of 1 to 12 carbon atoms, an aryl croup of 6 to 12 carbon atoms and an aralkyl group of 7 to 12 carbon atoms: wherein R 2 represents any of hydrogen, an alkyl group of 1 to 12 carbon atoms which may have a substituent, an alkenyl group of 2 to 12 carbon atoms which may have a substituent, an aryl group of 6 to 12 carbon atoms which may have a substituent, an aralkyl group of 7 to 12 carbon atoms which may have a substituent, a cyano group, a carboxyl group and an alkoxycarbonyl group; R 3 represents any of an alkyl group of 1 to 12 carbon atoms, an aryl group of 6 to 12 carbon atoms and an aralkyl group of 7 to 12 carbon atoms; and R 2 and R 3 may be joined to each other to form a ring , in the presence of a magnesium halide .