New Synthetic Routes to (+)-Uleine and (-)-Tubifolidine: General Approach to 2-Azabicyclo[3.3.1]nonane Indole Alkaloids.

Novel asymmetric synthetic routes to (+)-uleine and (-)-tubifolidine are reported herein. The regioselective formation of enol triflates from 2-azabicyclo[3.3.1]nonane ketones followed by indolizations of the resultant ene-hydrazides allowed the efficient construction of key indole intermediates, facilitating the total synthesis of the target natural alkaloids.