The first example of the Castagnoli-Cushman reaction of homophthalic acid with an amine and an aldehyde conducted in a three-component format is reported. This new protocol employs no dehydratingagents and, unlike the traditional Castagnoli-Cushman reaction of homophthalic anhydride, allows simultaneous mixing of all three reagents and provides good to excellent yields of trans-configured tetrahydroisoquinolonic
作者:Margarita Parra、Claudia Della Rosa、Salvador Gil、Pablo Rodríguez
DOI:10.1055/s-2006-950181
日期:——
addition of the dianions of carboxylic acids to isocyanates is presented. The use of sub-stoichiometric amounts of the amine in the generation of the dianion leads to an optimized process, which prevents the formation of urea derivatives due to the secondary reaction of isocyanates with the amine. This methodology is a new approach to the synthesis of β-aminoacids with better control of α-substitution