[CH3:1][CH2:2][O:3][C:4]([CH3:6])=[O:5].[Li+].CC([N-]C(C)C)C.[I:15][C:16]1[CH:24]=[CH:23][C:19]([C:20](Cl)=[O:21])=[CH:18][CH:17]=1.S(=O)(=O)(O)O>CCOCC>[I:15][C:16]1[CH:24]=[CH:23][C:19]([C:20](=[O:21])[CH2:6][C:4]([O:3][CH2:2][CH3:1])=[O:5])=[CH:18][CH:17]=1A solution of EtOAc (6 mL) in Et2O (15 mL) was added to a solution of LDA (2 M in THF, 60 mL, 120 mmol) in Et2O (80 mL) at −78° C. The resulting solution was stirred at −78° C. for 45 minutes. To this solution, a solution of 4-iodobenzoyl chloride (16 g, 60.5 mmol) in Et2O (30 mL) was added at −78° C. The reaction mixture was allowed to warm to room temperature and stirred for 15 h. The reaction mixture was poured into iced-sulfuric acid (300 g, 10%), stirred for 15 minutes, and extracted with Et2O (3×80 mL). The combined organic layers were dried over MgSO4 and concentrated in vacuo to afford the title compound as light orange oil (9 g, 47%). Compound exists as a mixture of ketone and enol forms (3:1). 1H NMR (CDCl3, 400 MHz): (ketone form) δ 7.87 (d, 2H), 7.67 (d, 2H), 4.26 (q, 2H), 3.95 (s, 2H), 1.24 (t, 3H); (enol form) δ 12.55 (s, 1H), 7.78 (d, 2H), 7.50 (q, 2H), 5.65 (s, 1H), 4.59 (q, 2H), 1.34 (t, 3H).
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