Fluoroalkyl-Substituted Diazomethanes and Their Application in a General Synthesis of Pyrazoles and Pyrazolines

Lucas Mertens; Katharina J Hock; Rene M Koenigs

doi:10.1002/chem.201601707

Fluoroalkyl-Substituted Diazomethanes and Their Application in a General Synthesis of Pyrazoles and Pyrazolines

Chemistry. 2016 Jul 4;22(28):9542-5. doi: 10.1002/chem.201601707. Epub 2016 Jun 6.

Authors

Lucas Mertens¹, Katharina J Hock¹, Rene M Koenigs²

Affiliations

¹ Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany.
² Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany. rene.koenigs@rwth-aachen.de.

PMID: 27168358
DOI: 10.1002/chem.201601707

Abstract

A novel continuous-flow approach for the synthesis of fluoroalkyl-substituted diazomethanes has been developed. Utilizing a cheap, self-made microreactor fluoroalkyl-substituted amines were transformed into the corresponding diazomethanes using tert-butyl nitrite and acetic acid as catalyst. These diazomethanes were employed in [2+3] cycloaddition reactions with olefins and alkynes, yielding valuable pyrazolines and pyrazoles in good to excellent yields.

Keywords: cycloaddition; diazo compounds; fluorine; heterocycles; microreactors.