Transition-metal-catalyzed The Synthesis Of Highly Substituted Functional Alkenes

We focused our study on transition-metal-catalyzed the synthesis of highly substituted functional alkenes, mainly including the following three parts in our work.Part 1:Preparation of highly substituted (β-Acylamino)acrylates via iron-catalyzed alkoxycarbonylation of N-vinylacetamides with carbazates.We have developed an iron-catalyzed alkoxycarbonylation reaction of N-vinylacetamides with carbazates under simple and mild reaction conditions. Various acyclic and cyclic N-vinylacetamides as starting materials were found to be tolerated in the titled reaction. The observed good steroselectivities and reasonable yields of the products make this method a general tool for synthesis of highly substituted (β-acylamino)acrylate derivatives via direct functionalization of N-vinylacetamides.Part 2:Direct methylation and benzylation of enamides with retention of alkenyl moiety using iodomethane and benzyl halides.We have described a palladium-catalyzed methylation and benzylation of enamides with iodomethane and various benzylic halides, and the corresponding products could be obtained in moderate to good yields, which provide a novel way to synthesize functional multisubstitued enamides.Part 3:Palladium-catalyzed cross-coupling of enamides with sterically hindered a-bromocarbonyls.A palladium-catalyzed alkylation reaction of enamides with α-bromo-substituted carbonyls has been developed, and the corresponding products could be obtained in good yields. Importantly, the β-hydride elimination side-reaction can be well suppressed under the optimized reaction conditions. The coupling products can be easily transformed into very useful y-amino acids,δ-amino alcohols,1,4-dicarbonyls and y-lactams with high efficiency.