1: methyl phosphonic acid,diethyl ester; benzonitrile With n-butyllithium in tetrahydrofuran; hexane T=-78 - -50°C; 0.5 h; 2: benzaldehyde in tetrahydrofuran; hexane T=-50 - 0°C; 0.75 h; 3: 5-amino-1H-pyrazole in tetrahydrofuran; N,N-dimethyl-formamide 8 h; Heating;

hydrogenchloride 3 h; Heating;