17° SEMINARIO QUÍMICA ORGÁNICA IQUIR 2020

SEMINARIO QUÍMICA ORGÁNICA 14-09-20

TÍTULO: "Enantioselective Total Synthesis of (+)-Corymine and (−)-Deformylcorymine"
FUENTE: Benxiang Zhang, Xiaoqing Wang, and Chaozhong Li. J. Am. Chem. Soc. 2020, 142, 3269−3274.

EXPOSITOR: Dra. Andrea B. J. Bracca

DÍA, HORA y LUGAR: Lunes 14 de septiembre de 2020, 18:00 h, Plataforma MEET GOOGLE.
Link: meet.google.com/bfh-poxv-bso

RESUMEN: We report herein the first enantioselective total synthesis of akuammiline alkaloids (+)-corymine and (−)-deformylcorymine. Starting from commercially available N-nosyltryptamine, the target molecules are both achieved in 11 steps. Key elements of the design include (a) a copper-catalyzed enantioselective addition of dimethyl malonate to a 3-bromooxindole to secure the C7 all-carbon quaternary stereocenter, (b) a one-step construction of cyclohexyl and pyrrolidinyl rings via intramolecular nucleophilic C- and N-addition, and (c) a nickel-promoted 7-endo cyclization of alkenyl bromide to furnish the azepanyl ring. The strategy is further extended to the synthesis of another three members of the akuammiline family, namely, (−)-10-demethoxyvincorine, (−)-2(S)-cathafoline, and (−)-3-epi-dihydrocorymine 17-acetate.