Cl[C:2]1[CH:7]=[CH:6][C:5]([S:8]([C:11]2[CH:16]=[CH:15][CH:14]=[CH:13][C:12]=2[F:17])(=[O:10])=[O:9])=[CH:4][N:3]=1.[CH2:18]([Sn](CCCC)(CCCC)C=C)[CH2:19]CC>O1CCCC1.C(OCC)(=O)C>[CH:18]([C:2]1[CH:7]=[CH:6][C:5]([S:8]([C:11]2[CH:16]=[CH:15][CH:14]=[CH:13][C:12]=2[F:17])(=[O:10])=[O:9])=[CH:4][N:3]=1)=[CH2:19]2-Chloro-5-[(2-fluorophenyl)sulfonyl]pyridine (Example 1 Steps 1 and 2, 410 mg, 1.52 mmol), tributyl(vinyl)tin (535 mg, 1.69 mmol) and tetrakis-(triphenylphosphine)palladium(0) (87 mg) were combined in tetrahydrofuran (10 mL) in three batches in 5 mL microwave vials. The vials were heated to 150° C. for 10 minutes in a Smith synthesiser microwave reactor. The combined reactions were diluted with ethyl acetate and washed with saturated aqueous ammonium chloride solution. The organic layers were dried over MgSO4 and concentrated in vacuo while loading onto silica. Dry flash column chromatography using 10-20% ethyl acetate/isohexane gave 2-vinyl-5-[(2-fluorophenyl)sulfonyl]pyridine as a colourless solid (265 mg, 66%). δH (500 MHz, d6 DMSO): 9.03 (1H, s), 8.30 (1H, dd, J=1.4, 8.3 Hz), 7.51 (1H, td, J=7.9, 0.85 Hz), 7.43 (1H, dd, J=9.1, 10.6 Hz), 6.92 (1H, dd, J=10.7, 17.4 Hz), 6.43 (1H, dd, J=1.2, 17.4 Hz), 5.70 (1H, dd, J=1.2, 10.7 Hz); m/z (ES+) 364 [MH+].
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