Hydrogen Bromide → 3-Amino-7-methoxy-5-phenyl-1H-benzo[e][1,4]diazepin-2(3H)-one

Participants

Reaction Steps

Intermediate 7B (0.5 g, 1.2 mmol) was treated with 3.5 mL (7 volumes) of 33% HBr in AcOH and was stirred at room temperature for 2 hrs. Diethyl ether (25 mL) was added to the reaction mixture and the precipitated solid was collected by filtration. The solid was dissolved in water (3 mL), and 10% sodium bicarbonate solution was added until the solution was basic. The product was extracted with 2×25 mL of ethyl acetate and the organic layer was dried over anhydrous sodium sulfate. The solvents were removed under vacuum to afford Intermediate 7C as a white solid: yield 0.32 g (98%). HPLC: RT=1.228 (H2O/ACN with NH4OAc, PUROSPHER® Star RP-18 (4×55) mm, 3 μm, gradient=3 min, wavelength=220 nm); MS(ES):m/z=282 [M+H+]; 1H NMR (DMSO-d6: δ 10.46 (brs, 1H), 7.42-7.53 (m, 5H), 7.19-7.25 (m, 2H), 6.72 (d, J=2.4 Hz, 1H), 4.25 (s, 1H), 3.39 (s, 3H).

Provenance & Evidence