反应详情

A mixture of 3-(3,5-dichlorophenyl)-2,4-dioxoimidazolidine-1-carboxylic acid tert-butyl ester (3.45 g, 10 mmol) (Preparation 11), 4-cyanobenzaldehyde (1.31 g, 10 mmol) and NaOAc (0.82 g, 10 mmol) was refluxed for 3 h in Ac2O (50 ml). The solid obtained after concentration was taken into a mixture of ice/water and DCM. The organic layer was dried and concentrated to yield a solid (4.4 g) which was chromatographed over silica gel (eluent: DCM) to yield 4-[3-acetyl-1-(3,5-dichlorophenyl)-2,5-dioxoimidazolidin-4-ylidenemethyl]-benzonitrile as a white solid (1.25 g). mp=212° C. 1H NMR (CDCl3): 8.52 (1H, s), 7.6-7.75 (4H, m), 7.43 (1H, m), 7.37 (2H, m), 2.78 (3H, s).

1. customThe solid obtained
2. concentrationafter concentration
3. additionwas taken into a mixture of ice/water and DCM
4. customThe organic layer was dried
5. concentrationconcentrated