反应详情

Concentrated hydrochloric acid (6.4 mL) was added to a solution of 4-(3-bromo-imidazo[1,2-b]pyridazin-6-yl)-piperazine-1-carboxylic acid tert-butyl ester 2.9 g, 7.6 mmol) in methanol (150 mL), allowed to stir at ambient temperature overnight, then evaporated to dryness. The resultant yellow solid was dissolved in methanol and the stirred solution diluted with diethyl ether to precipitate 3-bromo-6-piperazin-1-yl-imidazo[1,2-b]pyridazine dihydrochloride as 2.6 g of white powder, mp. 275-276° C. (dec.). 1H NMR (400 MHz, DMSO-d6) δ ppm 3.24 (br. s., 4H) 3.82-3.92 (m, 4H) 7.57 (d, J=10.11 Hz, 1H) 8.05 (s, 1H) 8.12 (d, J=10.10 Hz, 1H) 9.70 (br. s., 1H). 13C NMR (100 MHz, DMSO-d6) δ ppm 41.86, 42.37, 101.30, 114.15, 124.22, 127.20, 134.76, 155.43. LRMS (ESI) m/z 282.1/284.1 [(M+H)]+, calc'd for C10H12BrN5: 282.14.

1. customevaporated to dryness
2. dissolutionThe resultant yellow solid was dissolved in methanol
3. additionthe stirred solution diluted with diethyl ether
4. customto precipitate 3-bromo-6-piperazin-1-yl-imidazo[1,2-b]pyridazine dihydrochloride as 2.6 g of white powder, mp. 275-276° C. (dec.)