Asymmetric Catalytic Conjugate Addition of Acetaldehyde to Nitrodienynes/Nitroenynes: Applications to the Syntheses of (+)-α-Lycorane and Chiral β-Alkynyl Acids
The catalytic enantioselective conjugateaddition of acetaldehyde to polyconjugated substrates, nitrodienynes and nitroenynes, has been accomplished using organocatalysis. Various functionalized 1,3-enynes and propargylic compounds were obtained in moderate to good yields with high enantioselectivity. The synthetic utilities of the conjugateaddition reactions have been highlighted in the concise total