[CH2:1]([O:3][C:4]([C:6]1[CH:7]=[C:8]2[C:13](=[CH:14][CH:15]=1)[C:11](=[O:12])[O:10][CH2:9]2)=[O:5])[CH3:2].[CH3:16]C(O)C>>[CH3:2][CH:1]([O:3][C:4]([C:6]1[CH:7]=[C:8]2[C:13](=[CH:14][CH:15]=1)[C:11](=[O:12])[O:10][CH2:9]2)=[O:5])[CH3:16]Method B): 5-Ethoxycarbonylphthalid (52 g, 0.25 mole) is suspended in 2-propanol (1000 mL). Ti(iPro)4 (38 g, 0.14 mole) is added and the mixture is refluxed for 3 hours. The reaction mixture is cooled to 0° C. and the crystals are filtered off and washed with cold 2-propanol (70 mL). Yield: 47 g, 85%. DSC onset 144° C.
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