Sodium Bicarbonate → Tert-butyl 4-(((4-methyl-5-phenyl-4h-1,2,4-triazol-3-yl)methyl)(5,6,7,8-tetrahydroquinolin-8-yl)amino)butylcarbamate

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-methyl-5-phenyl-4H-1,2,4-triazole-3-carbaldehyde, 36, (0.41 g, 2.20 mmol) in 1,2-dichloroethane (4 mL) was added tert-butyl 4-(5,6,7,8-tetrahydroquinolin-8-ylamino)butylcarbamate, 3, (0.76 g, 2.40 mmol), sodium triacetoxyborohydride (0.84 g, 3.95 mmol), and AcOH (10 drops). The reaction mixture was heated to 65° C. and stirred for 18 h. The reaction mixture was cooled to room temperature and poured into saturated aqueous NaHCO3 (15 mL) and extracted with ethyl acetate (2×10 mL). The combined organic phases were washed with brine then dried over MgSO4, filtered, and concentrated in vacuo. The crude material was purified by silica gel chromatography (0-5% methanol/dichloromethane) to yield 37: 1H NMR (400 MHz, CDCl3) δ 8.40, (d, J=5.2 Hz, 1H), 7.60-7.57 (m, 2H), 7.48-7.44, (m, 3H), 7.31, (d, J=7.2 Hz, 1H), 7.0, (dd, J=8.0, 5.2 Hz, 1H), 5.01, (bs, 1H), 4.20-3.92, (m, 3H), 3.20-2.60, (m, 6H), 2.20-1.85, (m, 4H), 1.75-1.30 (m, 13H); ESI+ MS: m/z (rel intensity) 491 (100, M+H). Step g: Preparation of N-(4-aminobutyl)-N-((4-methyl-5-phenyl-4H-1,2,4-triazol-3-yl)methyl)-5,6,7,8-tetrahydroquinolin-8-amine tetrahydrochloride (BQ). Through a methanol (2 mL) solution of 37 (0.16 g, 0.32 mmol) was bubbled HCl(g) generated by the addition of sulfuric acid to dry NaCl. Upon total conversion of the reaction as monitored by LC-MS, the reaction mixture was concentrated in vacuo to yield BQ: ESI+ MS: m/z (rel intensity) 391 (100, M+H).

Provenance & Evidence