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N-(2-hydroxyethyl)phthalimide (19.12 g, 0.1 mol) was dissolved in anhydrous THF (250 mL) with triethylamine (28.1 mL, 0.2 mol) under nitrogen in a 500 mL round bottom flask equipped with a magnetic stirrer and dropping funnel. The flask was cooled to 0° C. with an ice/salt bath before the dropwise addition of 2-bromo-2-methylpropionyl bromide (13.9 mL, 0.11 mol). The mixture was stirred for 45 minutes and allowed to reach room temperature before the mixture was poured into an excess of cold water and the product extracted with diethyl ether (3×100 mL). The organic layer was subsequently washed with a saturated aqueous solution of sodium carbonate (3×100 mL), acidified water (pH 4.6, 3×100 mL) and again with saturated aqueous solution of sodium carbonate (3×100 mL). The organic layer was dried over anhydrous magnesium sulphate and filtered. The product was isolated via reduction under reduced pressure to obtain a white solid (25.79 g, 75.8% yield). 1H NMR (CDCl3) δ (ppm) 1.81 (s, 6H, C(CH3)2Br), 3.95 (t, 2H, J=5.3 Hz, CH2—N), 4.35 (t, 2H, J=5.4 Hz, CH2—O), 7.67 (m, 2H, Haro), 7.78 (m, 2H, Haro). 13C NMR (CDCl3) δ (ppm) 31.00 (2C, C(CH3)2Br), 37.12 (1C, CH2—N), 55.92 (1C, C(CH3)2Br), 63.42 (1C, CH2—O), 123.78 (2C, Caro), 132.35 (1C, CIVaro), 133.54 (2C, Caro), 168.40 (2C, Ccycl═O), 171.87 (1C, C═O). IR (solid, ATR cell) ν (cm−1) 2975, 1774 (Ccycl═O), 1705 (C═O), 1417, 1392, 1321, 1276, 1158, 1105, 1063, 985, 763, 716, 632. Melting point 63-65° C.

1. customequipped with a magnetic stirrer
2. customto reach room temperature before the mixture
3. extractionthe product extracted with diethyl ether (3×100 mL)
4. washThe organic layer was subsequently washed with a saturated aqueous solution of sodium carbonate (3×100 mL)
5. dry with materialThe organic layer was dried over anhydrous magnesium sulphate
6. filtrationfiltered
7. customThe product was isolated via reduction under reduced pressure