Palladium-Catalyzed Asymmetric Hydrogenation of 4-Substituted 3-Alkoxycarbonylfuran-2(5H)-ones

Palladium-catalyzed asymmetric hydrogenation of tetrasubstituted olefin 4-substituted 3-alkoxycar-bonylfuran-2(5H)-ones was developed for the construction of 1,2-contiguous stereogenters, giving the chiral trans-4-substituted 3-alkoxycarbonylbutyrolactone derivatives with up to 95% of enantioselectivities. The asymmetric hydrogenation reaction could proceed smoothly at gram scale without any loss of reactivity and enantioselectivity. In addition, the synthetic utility of the chiral reductive products has been demonstrated through useful building blocks.