Process for preparing alkyl esters of methyltartronic acid.

摘要

There is described a process for preparing alkyl esters of methyltartronic acid by hydroxylation of methacrylic acid to alpha-methylglyceric acid with H<Sub>2</Sub>0<Sub>2</Sub>, in an aqueous medium, in the presence of H<Sub>2</Sub>W0<Sub>4</Sub> and optionally of H<Sub>3</Sub>P0<Sub>4</Sub> or H<Sub>3</Sub>As0<Sub>4</Sub> or alkaline salts thereof as catalysts, at pH < 2 and at temperatures of from 50° to 100°C, by subsequent oxidation of alpha-methylglyceric acid to methyltartronic acid with HN0<Sub>3</Sub> in excess or with O<Sub>2</Sub>, in an aqueous-alkaline medium, in the presence of Pd or Pt carried on carbon or oxides thereof as catalysts, at temperatures of 60-100°C, and final esterification of methyltartronic acid with alcohols C<Sub>1</Sub>-C<Sub>4</Sub>.