hydrogenchloride in methanol; water T=20°C; 16 h;

1: 4-pyrazolylcarboxaldehyde With sodium hydride in N,N-dimethyl-formamide T=0°C; 0.25 h; 2: 2,2,2-trifluoro-ethanol 4-methylbenzenesulfonate in N,N-dimethyl-formamide T=6°C; 18 h;