[C:1]([Si:5]([CH3:14])([CH3:13])[O:6][C@H:7]1[CH2:11][CH2:10][C@H:9](O)[CH2:8]1)([CH3:4])([CH3:3])[CH3:2].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.[C:34]1(=[O:44])[NH:38][C:37](=[O:39])[C:36]2=[CH:40][CH:41]=[CH:42][CH:43]=[C:35]12.N(C(OCC)=O)=NC(OCC)=O>O1CCCC1>[C:1]([Si:5]([CH3:14])([CH3:13])[O:6][C@@H:7]1[CH2:11][CH2:10][C@H:9]([N:38]2[C:34](=[O:44])[C:35]3[C:36](=[CH:40][CH:41]=[CH:42][CH:43]=3)[C:37]2=[O:39])[CH2:8]1)([CH3:4])([CH3:3])[CH3:2]A solution of (±)-trans-3-(tert-butyl-dimethyl-silanyloxy)-cyclopentanol (1.1 g, 5.08 mmol) (from Example 10a supra), triphenylphosphine (3.2 g, 12.20 mmol) (Aldrich) and phthalimide (1.8 g, 12.20 mmol) (Aldrich) in anhydrous tetrahydrofuran (45 mL) was cooled to 0° C. To this was added dropwise diethyl azodicarboxylate (2.1 mL, 2.3 g, 12.20 mmol) (Aldrich) and the resulting solution was allowed to slowly warm to room temperature. After stirring overnight the reaction mixture was partitioned between ethyl acetate and water. The organic layer was collected, dried over sodium sulfate, filtered and concentrated and the residue was purified by chromatography on a silica gel column using a 0–35% ethyl acetate in hexanes gradient to give (±)-cis-2-[3-(tert-butyl-dimethyl-silanyloxy)-cyclopentyl]-isoindole-1,3-dione as a white solid. (Yield 1.52 g, 87%).
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