Hydrochloric Acid → 3-(2-{[(Tert-butoxy)carbonyl]amino}ethyl)benzoic acid

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Reaction Conditions

Reaction Steps

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

Provenance & Evidence