Direct synthesis of pyrazoles from esters using tert-butoxide-assisted C-(C=O) coupling

Chem Commun (Camb). 2015 Jun 4;51(44):9201-4. doi: 10.1039/c5cc02020d.

Abstract

This paper describes the direct synthesis of pyrazoles from esters that comprises two sequential reactions: tert-butoxide-assisted C-C(=O) coupling reaction to yield β-ketonitrile or α,β-alkynone intermediates, and condensation by hydrazine addition. The method reported allows for easy control of the regioselectivity and structure of substituents at N-1, C-3, C-4 and/or C-5 positions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Butanols / chemistry
  • Cyclization
  • Esters
  • Hydrazines / chemistry
  • Pyrazoles / chemistry*

Substances

  • Butanols
  • Esters
  • Hydrazines
  • Pyrazoles
  • hydrazine
  • tert-butoxide, potassium