8-BROMO-2,3,4,5-TETRAHYDRO-1H-PYRIDO[4,3-B]INDOLE

To a stirred solution of 4-bromophenylhydrazine hydrochloride (5.Og, 22.36 mmol) in ethanol (100 niL), piperidin-4-one hydrochloride (1.316g, 8.5984 mmol) was added and the mixture was heated to reflux. The reflux was maintained for 4 hours, then cooled to room temperature and dry hydrogen chloride gas was passed for 1 hour through the reaction mixture. The mixture was then again heated to reflux and maintained for 2h. After completion of reaction, ethanol was distilled off under vacuum and the residue was dissolved in water. The aqueous layer was neutralized with 2N sodium hydroxide solution and was extracted in dichloromethane (2 x 100 mL). The pH of the aqueous layer was then adjusted to 12.0 with 2N sodium hydroxide solution and the product was extracted with ethyl acetate. The ethyl acetate layer was dried over anhydrous sodium sulfate and concentrated under vacuum. The crude solid was washed with diethyl ether (50 mL) to obtain 8-bromo-2, 3, 4, 5-tetrahydro-lH-pyrido[4, 3-Compound 2 (1 g) was hydrolyzed by refluxing in ethanolic KOH (3.46 g in 10 mL ethanol) for 16 h. The reaction mixture was concentrated to remove ethanol and the residue was filtered and washed with water and ethanol, respectively, to give an off-yellow solid. The solid was dried, 700 mg, yield: 90.1percent.Compound 2 (1 g) was hydrolyzed by refluxing in ethanolic KOH (3.46 g in 10 mL ethanol) for 16 h. The reaction mixture was concentrated to remove ethanol and the residue was filtered and washed with water and ethanol, respectively, to give an off-yellow solid. The solid was dried, 700 mg, yield: 90.1%. 1H NMR (400 MHz, DMSO-d6) delta 10.93(br, 1H), 7.47(d, 1H, J=2.0 Hz), 7.22 (d, 1H, J=8.8 Hz), 7.09-7.07(m, 1H), 3.80 (s, 2H), 2.99 (t, 2H, J=5.6 Hz), 2.66 (t, 2H, J=5.6 Hz). 13C NMR (100 MHz, DMSO-d6) delta 135.25, 134.00, 127.45, 122.28, 119.35, 112.53, 110.68, 108.22, 42.82, 41.36, 24.02. MS (ESI) [M+H]+ MS (ESI), Calcd for, C11H12BrN2, 251.0: Found 251.1.

Molecular Weight:251.12
XLogP3:2.2
Hydrogen Bond Donor Count:2
Hydrogen Bond Acceptor Count:1
Exact Mass:250.01056
Monoisotopic Mass:250.01056
Topological Polar Surface Area:27.8
Heavy Atom Count:14
Complexity:221
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes