Asymmetric syntheses of (1R,1′R,5′R,7′R) and (1S,1′R,5′R,7′R)-1-hydroxy-exo-brevicomin and a formal synthesis of (+)-exo-brevicomin

Asymmetric syntheses of (1R,1′R,5′R,7′R) and (1S,1′R,5′R,7′R)-1-hydroxy-exo-brevicomins 1 and 2, volatiles of the male mountain pine beetle, and a formal synthesis of (+)-exo-brevicomin 3, a component of the attracting pheromone system of several bark beetles have been achieved. The key steps are Birch reduction of commercially available α-picoline, selective Wittig olefination, and Sharpless asymmetric dihydroxylation.