1: diethyl ether; zinc-powder; aqueous sulfuric acid / 40 °C 2: methanol View Scheme

1: p-aminobenzoic acid methyl ester With hydrogenchloride; sodium nitrite in water T=0°C; Inert atmosphere; 2: KSeCN With sodium acetate; sodium hydrogencarbonate in water T=0 - 55°C; Inert atmosphere;

hydrogenchloride; sodium acetate; sodium nitrite Diazotization.Reagens 4: Natriumhydrogencarbonat; Reagens 5: Wasser;