Efficient asymmetric synthesis of abeo-abietane-type diterpenoids by using the intramolecular Heck reaction.

The synthesis of the abeo-abietane-type diterpenoids, i.e., (-)-dichroanal B, (-)-dichroanone, and taiwaniaquinone H, was achieved by using the intramolecular asymmetric Heck reaction. Our synthetic routes required fewer steps and gave a much higher overall yield and ee within shorter steps than those for racemic and antipodal forms reported to date (10, 12, and 13 steps with an overall yield of 50%, 40%, and 39%, and 94%, 98%, and 98% ee, respectively).