Two Approaches to a Trifluoromethyl Triazole: A Fit-for-Purpose Trifluoromethylation in Flow-Mode and a Long-Term Decarboxylative Click Approach

Two approaches to a 1-aryl-4-trifluoromethyltriazole are described. Initially, a late-stage trifluoromethylation of the corresponding 1-aryl-4-iodotriazole using methyl fluorosulfonyldifluoroacetate (MDFA) was employed. However, the reaction was fraught with several safety and operational challenges, primarily due to the evolution of similar to 33 equiv of gas per equiv of substrate. While some of these challenges were either addressed or mitigated through operations in plug flow, the process remained low yielding and suboptimal. Subsequently, a more convergent, longer-term route involving a Cu-mediated decarboxylative Click reaction was developed.