A new vinylic organolithium reagent: An expedient C10+C10 synthesis of retinal

Abstract 2, 6-Dimethyl-8-methoxy-1-lithio-octatetra-1, 3, 5, 7-ene 4 is prepared by bromine-lithium exchange from its readily accessible bromo precursor 8 . The lithio reagent 4 reacts with carbonyl compounds to give in one pot, after a mild acidic hydrolysis, the retinoid aldehydes 2 .