[F:1][C:2]([F:9])(I)[C:3]([O:5][CH2:6][CH3:7])=[O:4].Br[C:11]1[N:12]=[N:13][C:14]([CH3:17])=[CH:15][CH:16]=1.O.[NH4+].[Cl-]>CS(C)=O.[Cu]>[F:1][C:2]([F:9])([C:11]1[N:12]=[N:13][C:14]([CH3:17])=[CH:15][CH:16]=1)[C:3]([O:5][CH2:6][CH3:7])=[O:4]
This procedure is derived from the general method of T. Taguchi, et al. (Tetrahedron Lett., 1986,27,6103-6106). Ethyl difluoroiodoacetate (0.355 mL, 651 mg, 2.60 mmol) was added to a rapidly stirred suspension of copper powder (333 mg, 5.24 mmol) in DMSO (6.5 mL) at RT. After 50 min., 3-bromo-6-methylpyridazine (300 mg, 1.73 mmol) was added in DMSO (1.0 mL). After 20 h, the mixture was transferred to a separatory funnel containing water (25 mL) and saturated aq. NH4Cl (25 mL), and extracted with EtOAc (2×50 mL). The organic extracts were washed with saturated aq. NaCl, dried (Na2SO4), decanted, and evaporated. Purification by flash column chromatography on silica gel, eluting with 70:30 v/v hexanes/EtOAc, gave 363 mg of the title compound as an amber liquid. For the title compound: 1H NMR (500 MHz, CDCl3) δ 7.79 (d, J=9, 1H), 7.53 (d, J=9, 1H), 4.43 (q, J=7, 2H), 2.82 (s, 3H), 1.38 (t, J=7, 3H).
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