It’s only fair to share… 4-Fluoropyrazoles are accessible in a single step from readily available aldehyde-derived N-alkylhydrazones through double C–H fluoroalkylation with tribromofluoromethane (CBr3F). RuCl2(PPh3)3 has been proven to be the most efficient catalyst for this transformation when compared to a range of other Cu-, Pd-, or Fe-based catalyst systems. Alexis Prieto Alexis Prieto, Didier Bouyssi*, and Nuno Monteiro* …