Cu-Catalyzed Enantioselective Boron Addition to N-Heteroaryl-Substituted Alkenes

Org Lett. 2017 Dec 15;19(24):6610-6613. doi: 10.1021/acs.orglett.7b03327. Epub 2017 Nov 27.

Abstract

Catalytic enantioselective Cu-B(pin) (pin = pinacolato) addition to N-heteroaryl-substituted alkenes followed by protonation promoted by phosphine-Cu complexes is presented. The resulting alkylboron products that contain a N-heteroaryl moiety are afforded in up to 97% yield and 99:1 enantiomeric ratio. The highly versatile C-B(pin) bond can be converted to a range of useful functional groups, delivering a variety of enantiomerically enriched building blocks that are otherwise difficult to access. The utility of this method is further demonstrated by application to a fragment synthesis of biologically active molecule U-75302. Preliminary mechanistic studies revealed that the adjacent N atom of the heterocycles plays a unique role in high reactivity and enantioselectivity.

Publication types

  • Research Support, Non-U.S. Gov't