An expedient route to a versatile intermediate for the stereoselective synthesis of all-trans-retinoic acid and beta-carotene

Article abstract of DOI:10.1016/0040-4039(93)88020-J

Base-catalyzed isomerization of vinyl phosphonate 5 afforded the corresponding allylic phosphonate (6) as the sole product. Horner-Emmons olefination of ethyl trans-3-methyl-4-oxo-2-butenoate with the ylide derived from 6 concludes a facile synthesis of t