Base-Free Photoredox/Nickel Dual-Catalytic Cross-Coupling of Ammonium Alkylsilicates

J Am Chem Soc. 2016 Jan 20;138(2):475-8. doi: 10.1021/jacs.5b10963. Epub 2015 Dec 24.

Abstract

Single-electron transmetalation is recognized as an enabling technology for the mild transfer of alkyl groups to transition metal catalysts in cross-coupling reactions. Hypercoordinate silicates represent a new and improved class of radical precursors because of their low oxidation potentials and the innocuous byproducts generated upon oxidation. Herein, we report the cross-coupling of secondary and primary ammonium alkylsilicates with (hetero)aryl bromides in good to excellent yields. The base-free conditions have exceptional protic group tolerance on both partners, permitting the cross-coupling of unprotected primary and secondary amines.

MeSH terms

  • Ammonium Compounds / chemistry*
  • Catalysis
  • Nickel / chemistry*
  • Oxidation-Reduction
  • Photochemical Processes*
  • Silicates / chemistry*

Substances

  • Ammonium Compounds
  • Silicates
  • Nickel