1: 4-bromo-1-phenyl-5-trifluoromethyl-1H-pyrazole With n-butyllithium; N,N,N',N'',N''-pentamethyldiethylenetriamine; diisopropylamine in tetrahydrofuran; hexane T=-75°C; 0.0833333 h; 2: carbon dioxide Further stages.;