[CH3:1][Mg]Cl.CON(C)[C:7](=[O:18])[CH2:8][C:9]1[CH:14]=[C:13]([F:15])[CH:12]=[C:11]([F:16])[C:10]=1[F:17]>C1COCC1>[F:17][C:10]1[C:11]([F:16])=[CH:12][C:13]([F:15])=[CH:14][C:9]=1[CH2:8][C:7](=[O:18])[CH3:1]A solution of CeCl3 (11.44 g, 0.045 mol) in THF (350 mL) was degassed for 1 h and heated to 45-50° C. for 5 h. When the solution was cooled to −10-5° C., MeMgCl (19.44 g, 0.26 mol) in THF was added and the mixture was stirred for 1 h at −10-5° C. After amide 43 (30.3 g, 0.13 mol) was charged into the reaction mixture at −10-5° C., the mixture was stirred for 5 h at 10-20° C. After the reaction was complete, the mixture was quenched by 1M HCl, and then partitioned with water and EtOAc. The organic phase was dried over Na2SO4 and concentrated. The crude residual was further purified by flash chromatography on silica gel (2-10% EtOAc/PE) to give 44 (20.8 g, 85% yield). 1H NMR (CDCl3, 400 MHz): δ 6.91-6.78 (m, 1H), 6.69 (dd, 1H), 3.77 (d, 2H), 2.25 (s, 3H); MS (ESI) m/e [M+H]+: 189.05.
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