Yield:175135-43-0 56%

Reaction Conditions:

with potassium carbonate;potassium iodide in N,N-dimethyl-formamide at 90; for 2 h;

Steps:

Synthesis of 4.5-dichloro-2-(2.6-dicHorobenzvDpyridazin-3(2HVone (G2-3)

Synthesis of 4.5-dichloro-2-(2.6-dicHorobenzvDpyridazin-3(2HVone (G2-3 To a solution of compound 4 (200 mg, 1.21 mmol), compound 26 (349 mg, 1.45 mmol) and K2CQ3 (335 mg, 2.42 rnnioi) in DMF (3 niL) was added J (20 mg, 0.12 mmol). The solution was stirred at 90 °C for 2h. The mixture was cooled to room temperature and quenched with water, extracted with EtOAc for 3 times, combined the organic layer, washed with brine, dried over Na_S04, filtered, concentrated under reduced pressure to give the crude product and washed with CH'OH to give compound G2-3 (220 mg, 56 %) as a brown solid. 'H NMR (CDCb, 300 MHz): δ 5.61 (s, 2H), 7.23-7.28 (m, IH), 7.35-7.38 (m, 2H), 7.67 (s, IH); LCMS [mobile phase: 30-95% Acetonitrile +0.02% NH40Ac] purity is >95%, Rt = 3.953 mim MS Calcd.: 324; MS Found: 325 (M+l)⁺.

References:

WO2015/143164,2015,A1 Location in patent:Page/Page column 117-118