Phosphorus oxychloride → Benzonitrile, 4-[8-(4-chlorophenyl)-5,6-dihydro-3-(MethoxyMethyl)-5-[[2-Methyl-6-(trifluoroMethyl)-3-pyridinyl]Methyl]-6-oxo-1,2,4-triazolo[4,3-b]pyridazin-7-yl]-

Participants

Reaction Conditions

Reaction Steps

N′-(4-(4-chlorophenyl)-5-(4-cyanophenyl)-1-((2-methyl-6-(trifluoromethyl)pyridin-3-yl)methyl)-6-oxo-1,6-dihydropyridazin-3-yl) -2-methoxyacetohydrazide (780 mg, 1.338 mmol) was dissolved in toluene (25 ml) and was heated at 120° C. for 15 min. After this time, POCl3(5 ml) was added and the reaction was stirred at 120° C. for an additional 2 hr. The reaction mixture was then cooled to room temperature and concentrated under reduced pressure. The resulting residue was dissolved in EtOAc (50 ml) and washed with saturated NaHCO3(20 ml), water (20 ml) and saturated NaCl (20 ml). The organic layer was dried (MgSO4), filtered and concentrated. The residue was purified using an ISCO automated system (80 g silica gel, 20%-80% EtOAc/Hex) to give the product 4-(8-(4-chlorophenyl)-3-(methoxymethyl)-5-((2-methyl-6-(trifluoromethyl)pyridin-3-yl)methyl)-6-oxo-5,6-dihydro-[1,2,4]triazolo[4,3-b]pyridazin-7-yl)benzonitrile (550 mg) as an off-white solid (73% yield). HPLC retention time 3.085 min (Method A); LCMS (M+H)=565.0. 1HNMR (CD3CN, 500 Hz) 7.67(1H, d, J=7.7Hz), 7.63(2H, d, J=8.8 Hz), 7.58(1H, d, J=7.75), 7.35-7.37(6H, m), 5.81(2H, s), 4.40(2H, s), 3.24(3H, s), 2.65(3H, s); 13CNMR (CD3CN, 500 Hz) 160.24, 157.25, 146.50(m), 146.00, 144.71, 139.15, 137.77, 135.93, 134.84, 134.25, 132.92, 132.64, 131.38, 129.26, 122.90(m), 119.25, 112.66, 65.06, 58.28, 50.01, 22.19.

Provenance & Evidence