Potassium Hydroxide → 2-((Tert-butoxycarbonyl)amino)-3,3-dimethylpent-4-enoic acid

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Reaction Conditions

Reaction Steps

To a round bottom flask was added ethyl 2-(tert-butoxycarbonylamino)-3,3-dimethylpent-4-enoate (280 mg, 1.03 mmol), EtOH (20 mL) and aqueous 1 N NaOH (5.16 mL, 5.16 mmol). The reaction was stirred at 70° C. overnight. The reaction was cooled to rt and KOH (232 mg, 4.13 mmol) was added and the reaction was stirred at rt for 3 days. The solvent was removed and the residue was dissolved in water (15 mL). The aqueous solution was washed with DCM (5 mL). The pH of the aqueous layer was then adjusted to <4 using aqueous 1 N HCl. Then, the aqueous solution was extracted with DCM (5×10 mL). The combined organic layers were washed with saturated aqueous NaCl (20 mL). The organic layer was separated, dried over MgSO4, filtered and concentrated to give 2-(tert-butoxycarbonylamino)-3,3-dimethylpent-4-enoic acid (240 mg, 0.986 mmol, 96% yield) as beige solid. 1H NMR (500 MHz, CDCl3) δ ppm 5.87 (dd, J=17.32, 10.72 Hz, 1H), 5.23-5.03 (m, 2H), 4.98 (d, J=8.25 Hz, 1H), 4.17 (d, J=8.80 Hz, 1H), 1.45 (s, 9H), 1.16 (d, J=4.40 Hz, 6H).

Provenance & Evidence