Copper-catalyzed (4+1) and (3+2) cyclizations of iodonium ylides with alkynes
Hao Liang1, Xiaobo He, Yaqi Zhang
1School of Chemistry, The Key Laboratory of Low-Carbon Chemistry & Energy Conservation of Guangdong Province, Sun Yat-Sen University, Guangzhou 510275, People's Republic of China. qiuliqin@mail.sysu.edu.cn.
Abstract:
The copper(ii)-catalyzed (4+1) cyclizations and copper(i)-catalyzed (3+2) cycloadditions of iodonium ylides and alkynes were successfully developed by employing efficient and safe iodonium ylides instead of traditional diazo compounds. Highly functionalized dimethyl (E)-3-benzylideneindoline-2,2-dicarboxylates and methyl 5-(2-hydroxyphenyl)-2-methoxy-4-phenylfuran-3-carboxylates were conveniently prepared in moderate to excellent yields. The possible reaction mechanisms were also discussed.
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