HBF₄/ACN: A simple and efficient protocol for the synthesis of pyrazoles under ambient reaction conditions

Abstract

An efficient and novel protocol for pyrazole synthesis has been developed by using fluoroboric acid as the acid catalyst. Simple and easily available 1,3-diketone and hydrazine derivatives are taken as the substrates for this purpose. The reaction entails mild reaction conditions and produces desired pyrazoles in good to excellent yields. Easy accessibility, easy handling, broad substrate scope, evading metal catalyst and economic viability make this protocol advantageous to most of the previously reported literature.

GRAPHICAL ABSTRACT

Keywords:

• Pyrazole
• fluoroboric acid
• hydrazine
• 13-diketone
• metal free

Supporting information

General Information, Experimental and Analytical data, ¹H and ¹³C NMR spectra and characterization data all are found in the “Supplementary Content” section of this article’s webpage.

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

D.S. is thankful to DST, New Delhi, India for a research grant [No. EMR/2016/002345]. Authors thank the Department of Science and Technology for financial assistance under DST-FIST program and UGC, New Delhi for Special Assistance Program (UGC-SAP) to the Department of Chemistry, Dibrugarh University.