The trans isomer of 2,3-dimethylbut-2-enedioic acid is called 2,3-dimethylfumaric acid, while its cis isomer is called 2,3-dimethylmaleic acid. 2,3-dihydroxy-2,3-dimethylsuccinic acid can also be called 2,3-dimethyltartaric acid.
Propose the synthesis that converts 2,3-dimethylfumaric acid into meso-2,3dimethyltartaric acid.