“…Very recently, Meng, Zhang, Chong and co-workers disclosed a methodology for the dual cobalt/organophotoredox regio-, diastereo-and enantioselective propargylation of alde- hydes, using readily accessible racemic propargyl carbonates (Scheme 69). [61] Optimized conditions consisted of a cobalt salt, chiral ligand, photocatalyst, terminal reductant (Hantzsch ester) and substoichiometric amount of DIPEA. Electron-rich, electronpoor, halogenated and sterically shielded (hetero)aryl aldehydes as well as primary, secondary and α-chiral aliphatic aldehydes were coupled in high yields and regio-, diastereo-and enantioselectivities.…”