Dicyclohexylcarbodiimide → Ethyl 4-(1,3-dioxoisoindolin-2-YL)-3-oxobutanoate

関与物質

反応手順

To a solution of 2-(1,3-dioxoisoindolin-2-yl)acetic acid (3.01 g, 14.67 mmol), 2,2-dimethyl-1,3-dioxane-4,6-dione (2.23 g, 15.47 mmol) and 4-dimethylaminopyridine (2.73 g, 22.35 mmol) in dichloromethane (150 mL) was added a solution of DCC (3.36 g, 16.28 mmol) in DCM (50 mL) at 0° C. The mixture was stirred at RT for 16 h. The insoluble materials were filtered off, and the filtrate was washed with 5% NaHSO4 aqueous solution. The organic phase was dried over anhydrous Na2SO4, filtered and the filtrate was concentrated under reduced pressure. The residue was treated with EtOH (200 mL) and the resulting mixture was stirred at 70° C. for 4 h and then concentrated under reduced pressure. Water was added to the residue and the mixture was extracted with EtOAc. The organic layers were washed with water and brine, dried over anhydrous MgSO4, and filtered. The filtrate was concentrated under reduced pressure and the residue was washed with IPE to give the title compound as a colorless solid (3.43 g, 85%). 1H NMR (400 MHz, CDCl3) δ ppm 1.31 (t, J=6.8 Hz, 3H), 3.58 (s, 2H), 4.24 (q, J=6.8 Hz, 2H), 4.67 (s, 2H), 7.73-7.78 (m, 2H), 7.86-7.91 (m, 2H).

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