Triethylamine → methyl 4-(9H-benzo[f]pyrido[2,3-b][1,2,4]triazolo[4,3-d][1,4]diazepin-3-yl)benzoate

Participants

Reaction Conditions

Reaction Steps

To a solution of 6-(methylthio)-11H-benzo[e]pyrido[3,2-b][1,4]diazepine (2.5 g, 10.4 mmol) in dichloromethane (50 mL) and methanol (20 mL) was added the methyl 4-(hydrazinecarbonyl)benzoate (4.02 g, 20.7 mmol) followed by triethyl amine (1 mL) and p-toluenesulfonic acid monohydrate (3.3 g, 17.3 mmol). The reaction mixture was stirred at 70° C. for 20 hours. The mixture was partitioned between water (100 mL) and dichloromethane (150 mL). The phases were separated and the organic phase was washed with water (50 mL) and brine (50 mL), dried over sodium sulfate, filtered and concentrated in vacuo. The residue was triturated from ethyl acetate, the solid filtered off and dried undet vacuum, yielding the methyl 4-(9H-benzo[f]pyrido[2,3-b][1,2,4]triazolo[4,3-d][1,4]diazepin-3-yl)benzoate as a yellow solid (1.7 g, 44%). M.p.>300° C.; 400 MHz 1H NMR (DMSO-d6) δ: 8.83 (s, 1H), 8.23 (dd, J=4.8, 1.6 Hz, 1H), 8.02 (dt, J=8.8, 1.8 Hz, 2H), 7.97 (dd, J=8.0, 1.6 Hz, 1H), 7.58 (dt, J=8.8, 1.8 Hz, 2H), 7.45 (td, J=5.1, 1.6 Hz, 1H), 7.35 (d, J=7.2 Hz, 1H), 7.2-7.1 (m, 2H), 6.91 (dd, J=8.4, 4.8 Hz, 1H), 3.88 (s, 3H); LCMS [M+H]: 370.

Provenance & Evidence