hydrogen; palladium 10 on activated carbon in methanol P=1551.49 Torr;

1: With lithium hydroxide in water; N,N-dimethyl-formamide T=45°C; 12 h; 2: With hydrogenchloride in water pH=5; 3: With copper(II) oxide in N,N-dimethyl-formamide T=160°C; 70 h;

(i) aq. NaNO2, H2SO4, (ii) (heating); Multistep reaction;

(i) HNO2, (ii) CuCl; Multistep reaction;