1: sodium methylate; 1-[2-(4-chlorophenyl)ethynyl]-1H-benzotriazole in acetonitrile T=65°C; Addition; 2 h; 2: ethanol With hydrogenchloride Hydrolysis; Further stages.;

1: 1-[2-(4-chlorophenyl)ethynyl]-1H-benzotriazole With sodium methylate in acetonitrile Heating; 2: ethanol With hydrogenchloride Heating; Further stages.;