Br[C:2]1[C:7]([F:8])=[CH:6][C:5]([S:9]([NH2:12])(=[O:11])=[O:10])=[CH:4][C:3]=1[F:13].[F-].[Cs+].[CH3:16]B(O)O>COCCOC.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[F:13][C:3]1[CH:4]=[C:5]([S:9]([NH2:12])(=[O:11])=[O:10])[CH:6]=[C:7]([F:8])[C:2]=1[CH3:16]
A mixture of 4-bromo-3,5-difluorobenzenesulfonamide (1.09 g, 4 mmol), CsF (1.34 g, 3 eq), methylboronic acid (494 mg, 2 equiv) and Pd(PPh3)4 (140 mg, 0.3 eq) in 1,2-dimethoxyethane (16 mL) was heated to 120° C. under microwave irradiation for 4 h. After cooling, solids were removed by filtration and washed with EtOAc. The filtrate was concentrated and then purified by column chromatography (silica, EtOAc-Hex, 1:4 to 4:1) to give 3,5-difluoro-4-methylbenzenesulfonamide (776 mg). 1H NMR (400 MHz, CD3OD) δ 7.65 (d, 2H), 2.46 (s, 3H); GC-MS (ES) m/z 207 (M).
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