Acetic Acid → HCID 67264249, compound

Participants

Reaction Steps

A solution of 1,1,2-(trimethoxy)ethane (2.0 g, 16.4 mmol) in TFA/H2O (5 mL, 1/1 vol.) was stirred for five minutes at 50° C. The mixture was cooled to room temperature and neutralized to pH 6-7 by the addition of microporous carbonate (MP-CO3) with stirring. This was filtered into a solution of 7-methoxy-8-nitro-1,3,4,5-tetrahydro-benzo[e][1,4]diazepin-2-one (375 mg, 1.58 mmol) in ethanol (40 mL). The MP-CO3 was washed further with ethanol (10 mL) into the reaction mixture. To this was added acetic acid (0.36 mL, 6.34 mmol) and the mixture was stirred for two hours at room temperature before being treated with sodium triacetoxyborohydride (2.0 g, 9.4 mmol) and stirred at room temperature for an additional 18 hours. The mixture was concentrated, dissolved in dichloromethane, washed with saturated aqueous sodium bicarbonate and brine, dried over magnesium sulfate, filtered and concentrated. Flash chromatography over silica gel (0-10% MeOH-EtOAc) gave 7-methoxy-4-(2-methoxy-ethyl)-8-nitro-1,3,4,5-tetrahydro-benzo[e][1,4]diazepin-2-one (175 mg, 38%); 1H NMR (400 MHz, DMSO-d6) δ 10.02 (s, 1H), 7.61 (s, 1H), 7.32 (s, 1H), 3.91 (s, 6H), 3.44 (t, J=6 Hz, 2H), 3.41 (s, 2H), 2.69 (t, J=6 Hz, 2H); MS (m/e) 296 (M+1).

Provenance & Evidence