反应详情

N-hydroxy phthalimide sodium salt (46.25 g.; 0.25 mol), is dissolved in dry DMF (220 ml), to the resulting suspension 38.8 g (0.25 mol) of N-methyl benzimidoyl chloride (prepared according to J. C. S. Perkin II, 1324, (1980)) are slowly added at room temperature, on stirring. The reaction mixture is stirred at room temperature for 19 h and then poured into 1.5 l of water. The so formed precipitate is sucked off and dried in vacuo to obtain 66.06 g of a a crude product which is then taken up in 250 ml of acetonitrile. After filtration 58.7 g of N-methyl-benzimidic acid 1,3-dioxo-1,3-dihydro-isoindol-2-yl ester are obtained in form of colorless crystals, mp. 174-176° C.

1. additionare slowly added at room temperature
2. stirringThe reaction mixture is stirred at room temperature for 19 h
3. customThe so formed precipitate
4. customdried in vacuo