[CH3:1][O:2][C:3]1[CH:12]=[CH:11][C:6]([C:7](NC)=[O:8])=[CH:5][CH:4]=1.C([Li])(CC)C.[CH:18](=O)[C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1.CCCCCC.C(OCC)(=[O:34])C>C1COCC1>[CH3:1][O:2][C:3]1[CH:12]=[C:11]2[C:6](=[CH:5][CH:4]=1)[C:7](=[O:34])[O:8][CH:18]2[C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1A solution of 8 (15 g, 91 mmol) in THF was cooled to −70° C. under Argon. To this was added sec-butyllithium (147 mL, 1.3M). After stirring 0.5 h a tan suspension resulted. Added benzaldehyde (9.2 mL, 91 mmol.) and stirred 1 h. Quenched with ice then removed THF in vacuo. Added sat. sodium bicarbonate and extracted with ethyl acetate (4×). Dried the combined organic portions with sodium sulfate (anh.) and removed the solvent in vacuo. Added toluene and heated to reflux for 18 h. Removal of the solvent in vacuo followed by trituration with hexane/ether gave unreacted starting material 8 (4.63 g). Concentration of the filtrate in vacuo followed by flash column chromatography (hexane:ethyl acetate 80:20) gave 9 as a yellow solid (12.0 g, 50.1 mmol, 55.1%)
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