Rhodium-Catalyzed Chemo-, Regio- and Enantioselective Hydroformylation of Cyclopropyl-Functionalized Trisubstituted Alkenes

Angew Chem Int Ed Engl. 2022 Aug 15;61(33):e202206577. doi: 10.1002/anie.202206577. Epub 2022 Jul 11.

Abstract

The first rhodium-catalyzed highly chemo-, regio- and enantioselective hydroformylation of cyclopropyl-functionalized trisubstituted alkenes affording useful chiral cyclopropyl entities is reported. Compared to generally used diphosphine ligands for asymmetric catalysis, the modified hybrid phosphorus ligand, named (R,S)-DTBM-Yanphos, can convert a series of readily available cyclopropyl-functionalized trisubstituted alkenes into high-value chiral cyclopropyl-functionalized aldehydes with high selectivities (81-98 % ee). Gram-scale reactions (TON up to 1500) and follow-up transformations to the corresponding alcohol, acid, esters and nitrile are also presented. Finally, a possible hydroformylation mechanism involving ring-open-hydroformylation pathways is proposed based on control and deuteroformylation reactions.

Keywords: Enantioselective; Hydroformylation; Regioselective; Rhodium; Trisubstituted Alkenes.