作者:Stephen C. Pelly、Christopher J. Parkinson、Willem A. L. van Otterlo、Charles B. de Koning
DOI:10.1021/jo051826s
日期:2005.12.1
The metathesis reaction is used as a key step for the synthesis of the indolo [2,3-a]carbazole core of rebeccamycin 13 and the sulfur analog of furostifoline 21. Using the same methodology for the attempted synthesis of furostifoline, we unexpectedly formed tert-butyl-2a-methyl-1,2,2a,10c-tetrahydro-6H-cyclobuta[c]furo[3,2-a]carbazole-6-carboxylate 26 from the unstable diene, tert-butyl 2-(2-isopropenyl-3-furyl)-3-vinyl-1H-indole-1-carboxylate 25, presumably via a spontaneous pi(8) electrocyclization reaction.