NO.[C:3]([C:7]1[CH:12]=[CH:11][C:10]([CH:13]([CH:17]([NH2:19])[CH3:18])[CH2:14][CH2:15]O)=[CH:9][CH:8]=1)([CH3:6])([CH3:5])[CH3:4].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.N(C(OCC)=O)=NC(OCC)=O>C1COCC1.C(O)(=O)C.CCCCCC>[C:3]([C:7]1[CH:12]=[CH:11][C:10]([CH:13]2[CH2:14][CH2:15][NH:19][CH:17]2[CH3:18])=[CH:9][CH:8]=1)([CH3:6])([CH3:5])[CH3:4]4.2 g (0.018 mol) of the aminoalcohol prepared in (c), 4.69 g (0.018 mol) of triphenylphosphine and 3.1 g (0.018 mol) of diethyl azodicarboxylate were dissolved in 100 mL THF. 2 drops of glacial acetic acid were added and the solution refluxed for two hours. During this time the initially red solution became yellow. On cooling, hexane was added dropwise until precipitation started. The mixture was then cooled in the freezer and the crystalline precipitate filtered off. The solvent was removed under reduced pressure and the residue taken up in chloroform and washed with water. The organic layer was dried with MgSO4, filtered, the solvent evaporated off under reduced pressure and the residue vacuum distilled (130° C. at 2 mm Hg) to afford 3.0 g (77 percent of theoretical) of the crude product in the form of a mobile oil. The NMR and IR spectra of the product were consistent with the expected structure and indicated a mixture of the two possible diastereoisomers were present in a ratio of 3:1.
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