Methanol → Methyl 2-[(tert-butoxycarbonyl)amino]pent-4-ynoate

Participants

Reaction Steps

Potassium carbonate (1.687 g, 12.2 mmol) was added to an anhydrous methanol (91.5 mL) solution of 2-tert-butoxycarbonylamino-4-oxo-butyric acid benzyl ester (1.875 g, 6.10 mmol) and the reaction stirred 10 minutes. (1-Diazo-2-oxo-propyl)-phosphonic acid dimethyl ester (1.407 g, 7.32 mmol) was added and the reaction was stirred at room temp temperature 1 hour. The reaction was poured into diethyl ether and washed 4 times with 5% sodium bicarbonate, dried over magnesium sulfate and concentrated (1.05 g, crude product mixture). The crude product was used directly in the next step. 1H NMR (400 MHz, CDCl3) δ5.39 -5.31 (m, 1H), 4.49-4.41 (m, 1H), 3.77 (s, 3H), 2.79-2.65 (m, 2H), 2.03 (s, 1H), 1.59 and 1.44 (2 singlets, rotamers, 3H).

Provenance & Evidence