Hydrogen bond assisted reactivity of Ylidineketonitriles with 1° amines: A chemoselective synthesis of 2-pyridone and 2-aminopyridine derivatives

Abstract

Ylidineketonitrile 2 with chlorodifluoromethyl (A = Cl) demonstrated a strong solvent dependence reaction with primary amines to form either 1-N-alkylated-3,5-disubstituted-2-pyridones or 2-N-alkylated-3, 5-trisubstituted pyridines. The methodology was tested for its scope with primary amines and synthesized 29 derivatives in good to excellent yield. Ylidineketonitrile 2e preferrentially forms pyridone derivatives in the majority of the solvents screened except trifluoroethanol, where chemoselective formation of 2-aminopyridine derivatives was observed.

GRAPHICAL ABSTRACT

Keywords:

• Chemoselective
• hydrogen bond
• pyridine
• pyridone
• Ylidineketonitriles

Acknowledgement

The authors would like to thank the Department of Chemistry, Mangalore University and Syngenta Biosciences Pvt. Ltd. Goa for providing opportunity to Damodar K. to carry out the above work as part of his PhD under the corporate PhD program.

Disclosure statement

The authors declare no conflict of interest.