C(N[CH:5]([CH3:7])[CH3:6])(C)C.[Li]CCCC.[C:13]([O:18][CH2:19][CH3:20])(=[O:17])C(C)C.[C:21](Cl)(=[O:33])[CH2:22][CH2:23][CH2:24][CH2:25][CH2:26][CH2:27][CH2:28][CH2:29][CH2:30][CH2:31][CH3:32]>CCOCC>[CH2:19]([O:18][C:13](=[O:17])[C:5]([CH3:6])([CH3:7])[C:21](=[O:33])[CH2:22][CH2:23][CH2:24][CH2:25][CH2:26][CH2:27][CH2:28][CH2:29][CH2:30][CH2:31][CH3:32])[CH3:20]To a cooled solution (-78° C.) of diisopropylamine (2.22 g, 0.022 mol) in 25 mL ether, n-BuLi (0.022 mol) was added dropwise and stirred for 20 minutes under a nitrogen atmosphere. Ethyl isobutyrate (2.65 g, 0.022 mol) was then added dropwise and the mixture was stirred for 20 minutes. In a separate flask, lauroyl chloride (5.0 g, 0.022 mol) was stirred in 10 mL ether and cooled to 0° C. The ethyl isobutyrate enolate solution was added dropwise to the lauroyl chloride solution over a 5-minute period. The reaction mixture was allowed to gradually warm to room temperature and stir for 16 hours (M. W. Rathke, et al, Tet. Lett., 2953 (1971)). The mixture was quenched with saturated ammonium chloride solution and extracted with ether two times. The combined organic layers were washed with brine, dried (MgSO4), and concentrated in vacuo (30° C.) to yield 6.5 g (0.021 mol, 98.9%) of the title compound.
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