Regioselective Oxidative Cleavage of Benzylidene Acetals: Synthesis of α‐ and β‐Benzoyloxy Carboxylic Acids

Ruthenium has twice the fun: The synthetic potential of the highly regio- and stereoselective title reaction, which relies on two oxidative cleavage steps promoted by RuCl3 in combination with NaIO4 (see example; Bz=benzoyl), was demonstrated with the synthesis of biologically active cis-(2R,3S)-3-hydroxypipecolic acid from D-glucose.