Lemon twist catalysis

Abstract

Organic Chemistry The limonene in citrus peels is a readily available and environmentally friendly chiral compound. Nonetheless, it lacks the functionality for direct use in most types of asymmetric catalysis. Nagata et al. report that when used as a solvent, limonene can bias the twist sense of an otherwise achiral polymer through subtle collective interactions. This polymer can then act as an asymmetric ligand, binding palladium at pendant phosphines to catalyze formation of binaphthyl compounds via Suzuki coupling in 98% enantiomeric excess. Asymmetric hydrosilylation was also demonstrated. ACS Cent. Sci. 10.1021/acscentsci.9b00330 (2019).