Isopropyl chloroformate → HCID 89802520, compound

Participants

Reaction Steps

Hunig's base [7087-68-5] (2.1 mL, 12.1 mmol) was added to an ambient temperature, stirred suspension of 3-bromo-6-(2-methylpiperazin-1-yl)imidazo[1,2-b]pyridazine dihydrochloride (1.1 g, 3.0 mmol) in ethyl acetate (150 mL). The suspension was stirred for 1.5 h then a 1.0M solution of isopropyl chloroformate in toluene (3.0 mL) was slowly added and the reaction allowed to proceed for 17 h then washed with brine. The ethyl acetate phase was dried (MgSO4) and evaporated. Product was purified by preparative RP-HPLC to provide 52.1 mg of racemic isopropyl 4-(3-bromoimidazo[1,2-b]pyridazin-6-yl)-3-methylpiperazine-1-carboxylate as a light yellow solid, mp. 52-54° C. 1H NMR (400 MHz, DMSO-d6) δ ppm 1.11 (d, J=6.57 Hz, 3H) 1.15-1.25 (m, 6H) 2.51 (dt, J=3.73, 1.80 Hz, 2H) 3.15 (dd, J=12.88, 2.78 Hz, 2H) 3.86 (d, J=13.39 Hz, 1H) 3.98 (d, J=13.39 Hz, 2H) 4.47 (br. s., 1H) 4.78-4.87 (m, 1H) 7.23 (d, J=10.10 Hz, 1H) 7.64 (s, 1H) 7.91 (d, J=10.11 Hz, 1H). 13C NMR (100 MHz, DMSO-d6) δ ppm 13.53, 21.90, 42.71, 48.04, 68.05, 99.42, 110.59, 126.00, 131.15, 136.33, 154.41, 154.71. LRMS (ESI) m/z 382.0/384.0 [(M+H)]+, calc'd for C16H20BrN6O2: 382.26.

Provenance & Evidence