[Br:1][C:2]1[CH:3]=[C:4]([C:8](=O)[CH3:9])[CH:5]=[N:6][CH:7]=1.[CH2:11]([S:13]([NH2:16])(=[O:15])=[O:14])[CH3:12].[CH3:17][Mg]Br>C1(C)C=CC=CC=1.CC(C)[O-].[Ti+4].CC(C)[O-].CC(C)[O-].CC(C)[O-]>[Br:1][C:2]1[CH:3]=[C:4]([C:8]([NH:16][S:13]([CH2:11][CH3:12])(=[O:15])=[O:14])([CH3:9])[CH3:17])[CH:5]=[N:6][CH:7]=1
A mixture of 1-(5-bromo-pyridin-3-yl)-ethanone (200 mg, 1.000 mmol), ethanesulfonamide (136 mg, 1.250 mmol) and titanium(IV) isopropoxide (586 μL, 2.0 mmol) in toluene (20 mL) was heated to reflux for 8 h. After concentration, the residue was dissolved in THF (5 mL). A solution of methylmagnesium bromide (1000 μl, 3.00 mmol) was added dropwise at −50° C. The resulting mixture was slowly warmed up to room temperature over a course of 2 h. The mixture was stirred at this temperature overnight and quenched with NH4Cl solution. After filtration, wash with CH2Cl2 and concentration, the residue was purified by flash column (Ethyl acetate/heptane, v/v, 10% to 50%) and yielded a yellow oil (35 mg). ESI-MS m/z: 309.1 [M+1]+, Retention time=1.22 min. 1H NMR (400 MHz, CDCl3): δ 1.43 (t, J=7.4 Hz, 3H), 1.84 (s, 6H), 2.98 (q, J=7.4 Hz, 2H), 5.07 (brs, 1H), 8.04 (s, 1H), 8.66 (s, 1H), 8.77 (s, 1H).
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