Asymmetric Synthesis of β-Substituted γ-Lactams via Rhodium/Diene-Catalyzed 1,4-Additions: Application to the Synthesis of (R)-Baclofen and (R)-Rolipram
摘要:
An efficient rhodium/diene-catalyzed asymmetric addition of arylboronic acids to alpha,beta-unsaturated gamma-lactams has been developed. The power of this methodology is further demonstrated by the concise synthesis of (R)-baclofen and (R)-rolipram.
Cooperative catalysts consisting of chiral Rh/Ag nanoparticles and Sc(OTf)3 have been developed that catalyze asymmetric 1,4‐addition reactions of arylboronic acids with α,β‐unsaturated amides efficiently. The reaction has been considered one of the most challenging reactions because of the low reactivity of the amide substrates. The new catalysts provide the desired products with outstanding enantioselectivities