[C:1]([O:22][CH:23]1[CH2:28][C:27]([CH3:30])([CH3:29])[NH:26][C:25]([CH3:32])([CH3:31])[CH2:24]1)(=[O:21])[C:2]1[C:3](=[CH:17][CH:18]=[CH:19][CH:20]=1)[C:4]([O:6][CH:7]1[CH2:12][C:11]([CH3:14])([CH3:13])[NH:10][C:9]([CH3:16])([CH3:15])[CH2:8]1)=[O:5].[C:33]([O:37]O)([CH3:36])([CH3:35])C>[Mo](=O)(=O)=O.C1CCCCC1>[C:4]([O:6][CH:7]1[CH2:8][C:9]([CH3:16])([CH3:15])[N:10]([O:37][CH:33]2[CH2:36][CH2:17][CH2:3][CH2:4][CH2:35]2)[C:11]([CH3:13])([CH3:14])[CH2:12]1)(=[O:5])[C:3]1[C:2](=[CH:20][CH:19]=[CH:18][CH:17]=1)[C:1]([O:22][CH:23]1[CH2:24][C:25]([CH3:32])([CH3:31])[N:26]([O:37][CH:33]2[CH2:36][CH2:20][CH2:2][CH2:1][CH2:35]2)[C:27]([CH3:30])([CH3:29])[CH2:28]1)=[O:21]A mixture of 30.0 grams (67.5 mmol) of di-(2,2,6,6-tetramethylpiperidin-4-yl) phthalate, 27.5 grams (214 mmol) of 70% aqueous tert-butyl hydroperoxide, 2.0 grams of molybdenum trioxide and 200 ml of cyclohexane is heated to reflux at 81° C. Water is collected in a Dean-Stark trap. After 75 minutes, the reaction mixture is red. Another portion of tert-butyl hydroperoxide (42.5 grams of 70% aqueous solution, 330 mmol) is added over 30 minutes. After additional water is collected in the trap, the reaction mixture is transferred to a Fischer-Porter bottle and heated at 140° C. for 4.5 hours. The nearly colorless reaction mixture is treated with 6.9 grams (69 mmol) of 90% aqueous tert-butyl hydroperoxide and heated at 140° C. for 90 minutes to remove the last traces of pink color. The reaction mixture is cooled, filtered and stirred with a solution of 43 grams of sodium sulfite in 530 ml of water for 2 hours. Methylene chloride (600 ml) is added and the organic layer is separated, dried over anhydrous magnesium sulfate and concentrated to a crude solid. Purification (Waters Prep. 500A HPLC, 25:1 heptane:ethyl acetate) affords 31.0 grams (72% yield) of the title compound as a white solid, melting at 149°-151° C.
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