[O:1]1[CH2:5][CH2:4][CH:3]([O:6][N:7]2C(=O)C3C(=CC=CC=3)C2=O)[CH2:2]1.NN.[CH3:20][O:21][C:22]1[CH:27]=[CH:26][C:25]([S:28](Cl)(=[O:30])=[O:29])=[CH:24][CH:23]=1.C(N(C(C)C)CC)(C)C>C1COCC1>[O:1]1[CH2:5][CH2:4][CH:3]([O:6][NH:7][S:28]([C:25]2[CH:24]=[CH:23][C:22]([O:21][CH3:20])=[CH:27][CH:26]=2)(=[O:30])=[O:29])[CH2:2]1
2-(tetrahydro-3-furanyloxy)-1H-isoindole-1,3(2H)-dione (1.5 mmol, 357 mg) was combined with hydrazine (1.7 mmol, 0.053 mL) in anhydrous THF (3 mL) under nitrogen. The reaction immediately formed a white suspension and was allowed to stir at room temperature for 1 hour. The suspension was filtered directly into a flask containing 4-methoxybenzenesulfonyl chloride (1.5 mmol, 316 mg) and diisopropylethylamine (1.8 mmol, 0.320 mL) was added. After stirring at room temperature for 18 hours, the reaction was concentrated to a solid. The resulting solid was partitioned between ethyl acetate and 1N HCl, and the organic layer was separated and washed with a saturated aqueous solution of sodium bicarbonate and brine, and dried over magnesium sulfate. The crude product was concentrated to a white solid and purified by silica gel chromatography (1:1 hexanes/ethyl acetate). The purified product was then combined with ether and filtered to remove the residual phthalimide-hydrazine biproduct. The filtrate was then crystallized by adding hexanes providing 203 mg (48%) white crystals. Rf=0.2 (1:1 hexanes/ethyl acetate); H1-NMR (CDCl3): δ 7.82 (2H,d), 6.99 (2H,d), 6.85 (1H,s), 4.82-4.79 (1H,m), 3.97-3.87 (2H,m), 3.87 (3H,s), 3.83-3.70 (2H,m), 2.12-1.99 (2H,m).
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