Convenient approaches to the selective syntheses of trifluoromethylated pyrazol-3-yl-
and pyrazol-5-ylphosphonates have been developed based on solvent- and metal-controlled
reaction of diethyl (4,4,4-trifluoro-3-oxobut-1-yn-1-yl)phosphonate and monosubstituted
hydrazines.
Key words
pyrazoles - phosphonates - cyclization - conjugated ynones - organofluorine compounds