β C-H functionalization of alkyl carboxylic acids is a highly valuable transformation but a very difficult one to achieve. Here, Zhe Zhuang and Jin-Qan Yu describes an innovative approach where the functionalization is achieved through the formation of a β-lactone intermediate using a combination of Pd(CH3CN)2Cl2 and a β-amino acid derivative as the catalytic system, TBHP as the oxidant and CsHCO3 as the base. The β-lactone can either be isolated or reacted with various nucleophiles such as Grignard reagents, halides or N-, O- and S-nucleophiles to access the β-substituted carboxylic acids.
To read the full article: https://www.nature.com/articles/s41586-019-1859-y