Bromide ion → Ether phthalimide

Participants

Reaction Steps

At 20° to 25° C., 190 ml (1.37 mol) of triethylamine was dripped over a period of 2.5 hours into a mixture of 283 g (1.30 mol) of the bromide prepared above, 1300 ml of N-methyl-2-pyrrolidone, 10 g of potassium iodide and 212 g (1.30 mol) of N-hydroxyphthalimide. After the mixture had been kept for 4 hours at 20° to 25° C., it was poured into 4000 ml of ice water, and 500 ml of 10% strength sodium hydroxide solution was added in portions. The mixture was extracted four times, each time with 500 ml of ethyl acetate. The combined ethyl acetate phases were washed neutral with dilute sodium hydroxide solution and water, dried over magnesium sulfate and evaporated down under reduced pressure. The crude product was purified chromatographically using 1000 g of silica gel/column 30×15 cm (developer: n-hexane/dichloromethane 7:3). There was obtained 113 g (29%) of phthalimide ether of melting point 69°-71° C. (isopropanol). 1H-NMR (250 MHz, d6 -DMSO): δ=2.55-2.70 (m, 2H), 4.28 (t, 2H), 6.00-6.20 (m, 1H), 6.77 (d, 1H), 7.00 (m, 2H), 7.35 (m, 1H), 7.87 (s, 4H).

Provenance & Evidence