Asymmetric Synthesis of All the Known Phlegmarine Alkaloids
作者:Bradley H. Wolfe、Adam H. Libby、Rima S. Al-awar、Christopher J. Foti、Daniel L. Comins
DOI:10.1021/jo1019688
日期:2010.12.17
The asymmetric synthesis of all four of the known natural phlegmarines and one synthetic derivative has been accomplished in 19−22 steps from 4-methoxy-3-(triisopropylsilyl)pyridine. Chiral N-acylpyridinium salt chemistry was used twice to set the stereocenters at the C-9 and C-2′ positions of the phlegmarine skeleton. Key reactions include the use of a mixed Grignard reagent for the second N-acylpyridinium