Dichloromethane → (E)-3-(4-(4-Methoxybenzyl)-2-oxo-2,3,4,5-tetrahydro-1H-pyrido[2,3-e][1,4]diazepin-7-yl)acrylic acid hydrochloride

Participants

Reaction Steps

A suspension of (E)-3-[4-(4-methoxy-benzyl)-2-oxo-2,3,4,5-tetrahydro-1H-pyrido[2,3-e][1,4]diazepin-7-yl]acrylic acid tert-butyl ester (3.54 g, 8.65 mmol) in CH2Cl2 (20 mL) was treated with TFA (20 mL). After stirring at room temperature under N2 for 25 min, the clear tan solution was concentrated in vacuo. The resulting residue was treated with anhydrous HCl (40 mL of a 4.0 M solution in dioxane, 160 mmol) and sonicated for 15 min. The solid was isolated by filtration, washed with Et2O and dried under vacuum at 50° C. for 3 d to give the title compound (3.40 g, 92%) as a white solid: 1H NMR (300 MHz, DMSO-d6) δ 12.38 (br s, 1H), 11.32 (s, 1H), 8.77 (s, 1H), 8.28 (s, 1H), 7.66-7.58 (m, 3H), 7.02 (d, J=8.6 Hz, 2H), 6.63 (d, J=16.1 Hz, 1H), 4.41-4.27 (m, 5H), 3.79 (s, 3H), 3.68 (s, 2H); MS (ESI) m/e 354 (M+H)+.

Provenance & Evidence