A process for preparing an alkyl phenylglycolic acid is disclosed. It
follows the sequence of condensing a substituted acetaldehyde with
mandelic acid to provide a 5-phenyl-1,3-dioxolan-4-one, which is condensed
with an alkyl ketone or aldehyde to provide a
5-(1-hydroxyalkyl)-5-phenyl-1,3-dioxolan-4-one, which is dehydrated to a
5-(1-alkenyl)-5-phenyl-1,3-dioxolan-4-one. The
5-(1-alkenyl)-5-phenyl-1,3-dioxolan-4-one may be hydrolyzed and reduced to
an .alpha.-alkylphenylglycolic acid or the hydrolysis and reduction steps
may be reversed. The process enables the production of single enantiomers
of cyclohexylphenylglycolic acid (CHPGA). An analogous process for racemic
CHPGA is disclosed employing racemic mandelic acid and acetone. Novel
intermediates in the process are also disclosed.