Cross-dehydrogenative coupling of azoles with α-C(sp3)-H of ethers and thioethers under metal-free conditions: functionalization of H-N azoles via C-H activation

J Org Chem. 2015 Feb 6;80(3):1929-36. doi: 10.1021/jo502477r. Epub 2015 Jan 28.

Abstract

A metal-free cross-dehydrogenative coupling method for the synthesis of N-substituted azoles has been developed. The TBAI/TBHP system catalyzed the coupling of azoles with ethers and thioethers via α-C(sp(3))-H activation. Under the optimized conditions, a diverse range of un/substituted azoles such as 1H-benzimidazole, 9H-purine, 1H-benzotriazole, 1H-1,2,3-triazole, 1H-1,2,4-triazole, and 1H-pyrazole were successfully employed for coupling with various ethers and thioethers such as tetrahydrofuran, tetrahydropyran, 1,4-dioxane, diethyl ether, tetrahydrothiophene, and 1,3-dithiolane.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Azoles / chemical synthesis*
  • Azoles / chemistry*
  • Catalysis
  • Ethers / chemistry*
  • Hydrogen Bonding
  • Metals / chemistry*
  • Molecular Structure
  • Sulfides / chemistry*
  • Triazoles / chemical synthesis*
  • Triazoles / chemistry*

Substances

  • Azoles
  • Ethers
  • Metals
  • Sulfides
  • Triazoles