Asymmetric Total Synthesis of Tacamonine (Pseudovincamone I) via Radical Cyclization

Article abstract of DOI:10.1021/jo00097a037

The radical cyclozations of (+/-)-(E)-3-((2-bromomethyl)butoxy)carbonyl)prop-2-enoates 11 and 12 and (+/-)-ethyl (E)-3--N-<2-(3-indolyl)ethyl>carbamoyl>prop-2-enoate (25) were carried out with (TMS)3SiH or Bu3SnH in the presence of AIBN. (-)-(2S)-2-((tert-Butyldimethylsilyloxy)methyl)butan-1-ol (6), which was prepared by two different methods, was converted into (+)-25.The radical cyclization of (+)-25 produced piperidinone 18 as a diastereomeric mixture, which was transformed into tacamonine (1).