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Broad-Scope (3 + 2) Cycloaddition of Cyclopropanes and Alkynes Enabled by Boronyl Radical Catalysis
Jingru Wen1, Zhengwei Ding2, Pengfei Li1,3
1Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, China.
Abstract:
Cyclopentene skeletons are ubiquitous in natural products and small molecule drugs. The (3 + 2) cycloaddition of cyclopropanes and alkynes represents an efficient and atom-economic strategy for synthesizing these structures. However, the types of substituents on cyclopropane and alkyne used in previous works show evident limitations, restricting the application of this type of reaction to some extent. Herein, we report a broad-scope (3 + 2) cycloaddition of cyclopropanes and alkynes catalyzed by boronyl radicals. In this method, various substrates, such as mono-, di-, tri-, and tetrasubstituted cyclopropanes, as well as mono- and disubstituted alkynes, were compatible with up to 98% isolated yield.
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