Hydrochloric Acid → (5-[(1S)-1-benzyloxycarbonylamino-ethyl]-3-benzyl-2-oxo-cyclohept-4-en-1-yl)-ethanoic acid

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Reaction Steps

To a stirred solution of the above ester (35) (1.2 g) in dioxane (12 mL) was added a solution of NaOH (5.3 mL, 1N in H2O). After stirring for 4 h at room temperature 1N HCl (5.3 mL) was added and the reaction extracted with ethyl acetate, washed with saturated NaCl, dried over MgSO4 and evaporated. The product (37) was obtained by flash chromatography (silica gel, 98:2:0.1 CHCl3 :MeOH:HOAc) (1.0 g, 86%). TLC Rf 0.53 (95:4:1 CHCl3 :MeOH:HOAc); MS DC I/NH3 (M+H)+ =436.3; 1H NMR (CDCl3) δ1.13(3H, d, J=7 Hz ), 1.6-3.3 (9H, m), 3.65 (1H, m), 4.1 (1H, br m), 5.1 (2H, s), 5.45(1H, d), 7.2(5H, s), 7.35(5H, s), 10.65 (1H, br s).

Provenance & Evidence