Total Synthesis of (+)-Corymine and (–)-Deformylcorymine

Key words

(+)-corymine - (–)-deformylcorymine - copper catalysis - nickel - Heck reaction

Significance

The authors report the first total synthesis of the two natural products (+)-corymine and (−)-deformylcorymine. These structurally complex alkaloids pose an interesting synthetic challenge due to their intriguing caged molecular structure.

Comment

Copper-catalyzed enantioselective substitution allows the preparation of malonate B. A sequence of four steps yields ketone D. Nickel-mediated Heck-type reaction gives access to F, which is subsequently transformed into the advanced intermediate G. This caged product can then be converted into (+)-corymine or (–)-deformylcorymine.