An Allenic Pauson-Khand Approach to 6,12-Guaianolides

作者:Grillet Francois; Huang Chaofeng; Brummond Kay M*
来源:Organic Letters, 2011, 13(23): 6304-6307.
DOI:10.1021/ol2028515

摘要

Cyclocarbonylation of alpha-methylene butyrolactone-containing allene-ynes affords 6,12-guaianolide ring systems. Incorporation of the a-methylene butyrolactone early in a synthetic sequence is rare for reactivity reasons; however, this moiety proves to be beneficial to the allenic Pauson-Khand reaction. The three double bonds and the ketone in the resulting 5-7-5 ring system bear significant differences in their reactivity and are ideally positioned for synthetic application to 6,12-guaianolides and analogs.