3-(2-AMINOETHYL)BENZOIC ACID synthesis

Yield:-

Reaction Conditions:

Stage #1: 3-(2-amino-ethyl)-benzoic acid ethyl esterwith sodium hydroxide in methanol;water at 40; for 6 h;
Stage #2: with hydrogenchloride in methanol;water;

Steps:

D.6

Ethyl 3-cyanomethyl-benzoate (compound E5) (7.15 g, 41 mmol) is dissolved in ethanol (200 mL) andconcentrated hydrochloric acid (5 ml), Pd/C (2 g) is added and the mixture is hydrogenated at 3 barhydrogen pressure for 24 h. Afterwards, the mixture is filtered, evaporated and the residue is treatedwith methanol (120 mL) and aqueous 2N NaOH (50 mL, 0.1 mol) and heated 6 h at 40 °C, filtered andthe filtrate treated with aqueous 2N hydrochloric acid (32 mL, 64 mmol). Boc-anhydride (Boc₂O) (9.81g, 45 mmol) and tertbutanol are added and stirred for 16 h at ambient temperature. The mixture isevaporated, ttoe residue is extracted with dichloromethane/ethyl acetate (1:1, 3 x 30 mL) and water.After evaporation the organic phase is purified by flash chromatography.Yield: 1.73 g (16%) mp: 121-123 °C

References:

WO2006/589,2006,A1 Location in patent:Page/Page column 55