benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine in dichloromethane T=20°C; 8 h;

1: benzene-1,3-dicarboxylic acid monomethyl ester With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine in tetrahydrofuran; DMF (N,N-dimethyl-formamide) T=20°C; 0.25 h; 2: n-dipropylamine in tetrahydrofuran; DMF (N,N-dimethyl-formamide) T=20°C; 16 h;

1: 95.7 percent / SOCl2 / 72 h / 20 °C 2: 99.2 percent / KOH / methanol / 15 h / 20 °C 3: 92 percent / EDAC; HOBt; Et3N / CH2Cl2 / 8 h / 20 °C View Scheme

1: 99.2 percent / KOH / methanol / 15 h / 20 °C 2: 92 percent / EDAC; HOBt; Et3N / CH2Cl2 / 8 h / 20 °C View Scheme

in dichloromethane T=0 - 20°C;

1: With lithium hydroxide hydrate in 1,4-dioxane; water T=0°C; 2: With sulfuric acid in 1,4-dioxane; water; ethyl acetate