Mild Ring-Opening 1,3-Hydroborations of Non-Activated Cyclopropanes

Di Wang; Xiao-Song Xue; Kendall N Houk; Zhuangzhi Shi

doi:10.1002/anie.201811036

Mild Ring-Opening 1,3-Hydroborations of Non-Activated Cyclopropanes

Angew Chem Int Ed Engl. 2018 Dec 17;57(51):16861-16865. doi: 10.1002/anie.201811036. Epub 2018 Nov 21.

Authors

Di Wang¹, Xiao-Song Xue^{2

3}, Kendall N Houk², Zhuangzhi Shi¹

Affiliations

¹ State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, China.
² Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, 90095, USA.
³ State Key Laboratory of Elemento-organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China.

PMID: 30370972
DOI: 10.1002/anie.201811036

Abstract

The Brown hydroboration reaction, first reported in 1957, is the addition of B-H across an olefin in an anti-Markovnikov fashion. Here, we solved a long-standing problem on mild 1,3-hydroborations of non-activated cyclopropanes. A three-component system including cyclopropanes, boron halides, and hydrosilanes has been developed for borylative ring-opening of cyclopropanes following the anti-Markovnikov rule, under mild reaction conditions. Density functional theory (M06-2X) calculations show that the preferred pathway involves a cationic boron intermediate which is quenched by hydride transfer from the silane.

Keywords: C−C activation; DFT calculations; cyclopropanes; hydroboration; metal-free synthesis.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.