Fluoroalkyl-Substituted Diazomethanes and Their Application in a General Synthesis of Pyrazoles and Pyrazolines.
Lucas MertensKatharina J HockRené M KoenigsPublished in: Chemistry (Weinheim an der Bergstrasse, Germany) (2016)
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.