Regio- and Stereoselective Synthesis of 1,2-Dihaloalkenes Using In-Situ-Generated ICl, IBr, BrCl, I2, and Br2

Xiaojun Zeng; Shiwen Liu; Yuhao Yang; Yi Yang; Gerald B Hammond; Bo Xu

doi:10.1016/j.chempr.2020.03.011

Regio- and Stereoselective Synthesis of 1,2-Dihaloalkenes Using In-Situ-Generated ICl, IBr, BrCl, I2, and Br2

Chem. 2020 Apr 9;6(4):1018-1031. doi: 10.1016/j.chempr.2020.03.011.

Authors

Xiaojun Zeng¹, Shiwen Liu², Yuhao Yang¹, Yi Yang², Gerald B Hammond^{1

3}, Bo Xu²

Affiliations

¹ Department of Chemistry, University of Louisville, Louisville, KY 40292, USA.
² College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620, China.
³ Lead Contact.

Abstract

We describe a catalyst-free 1,2-trans-dihalogenation of alkynes with an unprecedented substrate scope and exclusive regio- and stereoselectivity. This versatile dihalogenation system-a combination of NX¹S electrophile and alkali metal halide (MX²) in acetic acid-is applicable for diverse categories of alkynes (electron-rich or poor alkynes, internal and terminal alkynes, or heteroatoms such as O-, N-, S-substituted alkynes). The hydrogen bonding donor solvent acetic acid is essential for the in-situ generation of X¹X² electrophile, including ICl, IBr, BrCl, I_2, and Br₂.

Grants and funding

R01 GM121660/GM/NIGMS NIH HHS/United States