Scalable Total Synthesis of Jungermannenones B and C

Weilong Liu, Houhua Li, Peijun Cai, Zhen Wang, Zhi-Xiang Yu, and Xiaoguang Lei*
Angew. Chem. Int. Ed. 2016, 55, 3112-3116

Abstract:We report the first scalable synthesis of rac-jungermannenones B (1) and C (2) starting from commercially available inexpensive geraniol (8) in 10 and 9 steps, respectively. The unique jungermannenone framework is rapidly assembled by an unprecedented regioselective 1, 6-dienyne reductive cyclization reaction which proceeds via a vinyl radical cyclization-allylic radical isomerization mechanism. DFT calculations explain […]

Abstract:We report the first scalable synthesis of rac-jungermannenones B (1) and C (2) starting from commercially available inexpensive geraniol (8) in 10 and 9 steps, respectively. The unique jungermannenone framework is rapidly assembled by an unprecedented regioselective 1, 6-dienyne reductive cyclization reaction which proceeds via a vinyl radical cyclization-allylic radical isomerization mechanism. DFT calculations explain the high regioselectivity observed in the remarkable 1, 6-dienyne reductive radical cyclization.

http://onlinelibrary.wiley.com/doi/10.1002/anie.201511659/full