[Li]C(CC)C.C1CCCCC1.C(=O)=O.CC(C)=O.[CH2:19]([N:21]([CH2:31][CH3:32])[C:22](=[O:30])[C:23]1[CH:28]=[CH:27][CH:26]=[CH:25][C:24]=1[Cl:29])[CH3:20].[CH3:33][Ge:34]([CH3:37])([CH3:36])Cl>C1COCC1.CCOCC>[Cl:29][C:24]1[CH:25]=[CH:26][CH:27]=[C:28]([Ge:34]([CH3:37])([CH3:36])[CH3:33])[C:23]=1[C:22]([N:21]([CH2:19][CH3:20])[CH2:31][CH3:32])=[O:30]A solution of 1.3M s-BuLi in cyclohexane (21.8 mL, 28.3 mmol) was added dropwise to a dry ice/acetone cooled solution of the compound of example e (4.6 g, 21.7 mmol) in THF (60 mL), maintaining the internal reaction temperature ≤-65° C. This mixture was stirred at -78° C. for 45 min, then was quenched by the dropwise addition of a solution of trimethylchlorogermane (5.0 g, 32.6 mmol) in THF (30 mL), again maintaining the internal reaction temperature ≤-65° C. The reaction was warmed to 0° C., diluted with ether, and extracted with 10% HCl (2×) followed with sat aq NaHCO3. The ether was dried (MgSO4), concentrated, and purified by HPLC with 6% EtOAc in hexanes to afford 3.2 g of the title compound as a white solid, a 45% yield. m.p. 47-48° C.
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