Heterogeneous catalytic dehydrogenative coupling of ethylene glycol and primary alcohols intoα-hydroxycarboxylic acids

Lactic acid and otherα-hydroxycarboxylic acids(α-HCAs)play crucial roles in various applications.Synthesizingα-HCAs from biomass platform feedstocks such as ethylene glycol(EG)and primary alcohols is novel and attractive.It was reported that the dehydrogenative cross-coupling of EG and primary alcohols can be achieved via homogeneous catalysis.Herein,we report a heterogeneous catalytic strategy to produce a series ofα-HCAs through the same reaction pathway.Impressive catalytic activity and selectivity were achieved using various metals(Ru,Ir,Pt and Pd)supported on the nanodiamond-graphene(ND@G),with Ru exhibiting the best performance.This universally applicable process enables the easy synthesis of gram-scaleα-HCAs,providing a straightforward and compelling C–C bond cross-coupling strategy for the utilization of alcohols derived from biomass feedstocks.