A rhodium(I)-catalyzed formal allenic Alder ene reaction for the rapid and stereoselective assembly of cross-conjugated trienes

A rhodium(I)-catalyzed allenic Alder ene reaction to prepare cross-conjugated trienes has been discovered. The scope and limitations are currently being investigated, and the results obtained to date are reported on. This method shows enticing functional group compatibility by tolerating terminal and internal alkynes, hydroxyl, sulfonamide, ether, and diester groups. Progress has been made to increase the stereoselectivity of the olefinic side chain via an unprecendented iridium(I) catalyzed Alder-ene reaction.