1: With sodium hydroxide; water in ethanol T=20°C; 2 h; 2: With hydrogenchloride in ethanol; water pH=6 - 7;

1: 4-amino-benzoic acid ethyl ester With tert.-butylnitrite; acetic acid in N,N-dimethyl-formamide T=20°C; 0.0833333 h; Inert atmosphere; 2: para-bromophenylboronic acid With tris-(dibenzylideneacetone)dipalladium(0); trifuran-2-yl-phosphane in N,N-dimethyl-formamide T=90°C; 10 h; Inert atmosphere;

sulfuric acid T=130°C; 10 h;

1: AlCl3, aluminium chloride / dichloromethane 2: hydrogenchloride; bromine; sodium hydroxide 3: sulfuric acid View Scheme

1: hydrogenchloride; bromine; sodium hydroxide 2: sulfuric acid View Scheme