Tetravinylstannane → 3-Isopropyl-6-vinyl-[1,2,4]triazolo[4,3-b]pyridazine

Participants

Reaction Conditions

Reaction Steps

The 6-chloro-3-isopropyl-[1,2,4]triazolo[4,3-b]pyridazine (8.60 g, 43.7 mmol, Preparation #G.1), tetravinylstannane (11.91 g, 52.50 mmol), PdCl2(PPh3)2 (3.07 g, 4.37 mmol) and lithium chloride (3.71 g, 87.0 mmol) were added to DMF (65 mL) and then the mixture was heated to about 85° C. for about 1 h. The reaction was cooled to ambient temperature and then concentrated under reduced pressure. Water and EtOAc were added to the residue and then the mixture was filtered through Celite®. The filtrate was transferred to a separatory funnel and the layers were separated then the aqueous layer was extracted with EtOAc. The combined organic solutions were dried over MgSO4 and filtered prior to concentrating under reduced pressure to provide an oil which was purified by flash chromatography on silica gel with EtOAc as an eluent. The material was purified further by flash chromatography on silica gel with DCM/MeOH (95:5) as an eluent to give the title compound (3.28 g, 39.8%) as a light yellow oil which crystallized on standing: 1H NMR (DMSO-d6) δ 1.39 (d, 6H), 3.53 (m, 1H), 5.84 (d, 1H), 6.44 (d, 1H), 6.82 (dd, 1H), 7.69 (d, 1H), 8.28 (d, 1H); LC/MS (Table 1, Method a) Rt=2.06 min; MS m/z: 189.2 (M+H)+.

Provenance & Evidence