4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c]pyridine → 2-(Di-tert-butoxycarbonylamino)-3-(1,4,6,7-tetrahydro-pyrazolo[4,3-c]pyridin-5-yl)-propionic acid methyl ester

Participants

Reaction Steps

To a solution of 4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c]pyridine (160 mg) in 2.5 mL methanol was added 2-(di-tert-butoxycarbonylamino)-acrylic acid methyl ester (400 mg). The reaction was concentrated to approximately 1.5 mL by application of a gentle stream of nitrogen. The solution was stirred at room temperature overnight. The reaction was concentrated, dissolved in ethyl acetate, washed with brine, dried over magnesium sulfate, and concentrated. The resulting residue was pure enough to use without purification. 1H-NMR (CDCl3, 500 MHz) δ 1.44 (s, 9H), 2.73 (m, 3H), 2.91 (m, 1H), 3.06 (dd, J=13.4, 8.6, 1H), 3.22 (dd, J=13.4, 8.2, 1H), 3.54 (d, J=13.4, 1H), 3.63 (d, J=13.4, 1H), 3.71 (s, 3H), 5.11 (dd, J=8.5, 5.2, 1H), 7.25 (s, 1H). Mass spec.: 425.23 (MH)+.

Provenance & Evidence