1,8-Diazabicyclo(5.4.0)undec-7-ene → [3-(3-Bromo-imidazo[1,2-b]pyridazin-6-ylamino)-propyl]-methyl-carbamic acid tert-butyl ester

Participants

Reaction Steps

Acetonitrile (16.0 mL) was added to a mixture of 3-bromo-imidazo[1,2-b]pyridazin-6-one (344.3 mg, 1.6 mmol) and (benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP reagent) [56602-33-6], the mixture allowed to stir to effect dissolution. A solution of (3-amino-propyl)-methyl-carbamic acid tert-butyl ester [150349-36-3] (0.8 g, 3.98 mmol) and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) [6674-22-2] (2.4 mL, 2.4 mmol) in DMF (4.0 mL) was added and the reaction allowed to stir at ambient temperature for 3d. The reaction solution was partitioned between brine and ethyl acetate, dried (MgSO4), and flash chromatographed (silica gel, eluted with 10% (v/v) 2-propanol/ethyl acetate) to provide [3-(3-bromo-imidazo[1,2-b]pyridazin-6-ylamino)-propyl]-methyl-carbamic acid tert-butyl ester as 0.4 g of clear yellow oil. LRMS (ESI) m/z 384.1/386.1 [(M+H)]+, calc'd for C16H22BrN6O2: 384.28.

Provenance & Evidence