Palladium-catalyzed double annulations to construct multisubstituted benzodifurans.
Efficient synthetic routes to construct multisubstituted benzo[1,2-b:5,4-b']difurans and benzo[1,2-b:4,5-b']difurans from bis(allyloxy)bis(alkynyl)benzenes or bis(alkynyl)dihydroxybenzenes and allylic halides utilizing palladium-catalyzed double annulations is reported. By further applying a double ring-closing metathesis reaction, pentacyclic compounds were also prepared.
Liang
Zhiqiang
Z
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, PR China.
Ma
Shengming
S
Yu
Jihong
J
Xu
Ruren
R