Process for producing optically active carboxylic acid substituted in 2-position

A method of producing an optically active 2-chlorocarboxylic acid represented by the general formula (2):

• in which R1 represents a substituted or unsubstituted aryl group containing 6 to 14 carbon atoms or a substituted or unsubstituted aralkyl group containing 7 to 15 carbon atoms, which comprises reacting an optically active 2-hydroxycarboxylic acid represented by the general formula (1):
• in which R1 is as defined above,
• with thionyl chloride and an organic base for chlorination with inversion of the configuration at 2-position,
• wherein the rate of configurational inversion in the step of chlorination with inversion of configuration is not less than 95%, and
• hydrolyzing the thus-obtained optically active 2-chlorocarboxylic acid chloride represented by the general formula (5):
• in which R1 is as defined above wherein at least one solvent selected from among ether solvents is used as the reaction solvent for chlorination with inversion of configuration.

A method of producing an optically active 2-chlorocarboxylic acid chloride represented by the general formula (5):

• in which R1 represents a substituted or unsubstituted alkyl group containing 1 to 12 carbon atoms, a substituted or unsubstituted aryl group containing 6 to 14 carbon atoms or a substituted or unsubstituted aralkyl group containing 7 to 15 carbon atoms, which comprises reacting an optically active 2-hydroxycarboxylic acid represented by the general formula (1):
• in which R1 is as defined above,
• with thionyl chloride and an amide group-containing compound for chlorination with inversion of the configuration at 2-position,
• wherein the rate of configurational inversion in the step of chlorination with inversion of configuration is not less than 95%.

A method of producing an optically active 2-chlorocarboxylic acid chloride represented by the general formula (5):

• in which R1 represents a substituted or unsubstituted alkyl group containing 1 to 12 carbon atoms, a substituted or unsubstituted aryl group containing 6 to 14 carbon atoms or a substituted or unsubstituted aralkyl group containing 7 to 15 carbon atoms,
• which comprises reacting an optically active 2-hydroxycarboxylic acid represented by the general formula (1):
• in which R1 is as defined above, with thionyl chloride and a quaternary ammonium halide for chlorination with inversion of the configuration at 2-position,
• wherein the rate of configurational inversion in the step of chlorination with inversion of configuration is not less than 95%.

A method of producing an optically active 2-chlorocarboxylic acid represented by the general formula (2):

• in which R1 represents a substituted or unsubstituted alkyl group containing 1 to 12 carbon atoms, a substituted or unsubstituted aryl group containing 6 to 14 carbon atoms or a substituted or unsubstituted aralkyl group containing 7 to 15 carbon atoms,
• which comprises reacting an optically active 2-hydroxycarboxylic acid represented by the general formula (1):
• in which R1 is as defined above,
• with thionyl chloride and an amide group-containing compound for chlorination with inversion of the configuration at 2-position,
• wherein the rate of configurational inversion in the step of chlorination with inversion of configuration is not less than 95%, and
• hydrolyzing the thus-obtained optically active 2-chlorocarboxylic acid chloride represented by the general formula (5):
• in which R1 is as defined above.

A method of producing an optically active 2-chlorocarboxylic acid represented by the general formula (2):

• in which R1 represents a substituted or unsubstituted alkyl group containing 1 to 12 carbon atoms, a substituted or unsubstituted aryl group containing 6 to 14 carbon atoms or a substituted or unsubstituted aralkyl group containing 7 to 15 carbon atoms,
• which comprises reacting an optically active 2-hydroxycarboxylic acid represented by the general formula (1):
• in which R1 is as defined above,
• by reaction with thionyl chloride and a quaternary ammonium halide for chlorination with inversion of the configuration at 2-position,
• wherein the rate of configurational inversion in the step of chlorination with inversion of configuration is not less than 95%, and
• hydrolyzing the thus-obtained optically active 2-chlorocarboxylic acid chloride represented by the general formula (5):
• in which R1 is as defined above.