Chiral Induction by Elimination‐Coupled Lithium–Ene Reaction: Synthesis of (+)‐(3
R
,4
R
)‐1,2‐Dihydromultifidene
摘要:
Cyclization of the alkadienyl carbamates 1 to the cis-divinylcyclopentanes 2 with high enantioselectivity and diastereoselectivity has been successfully achieved by (-)-sparteine-induced asymmetric deprotonation. The conversion may be described as a hybrid of a lithium-ene reaction and an Sn ' reaction.