Water → 3-(3,5-Dichlorophenyl)-2,4-imidazolidinedione

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a suspension of 3-(3,5-dichlorophenyl)-ureidoacetic acid (813 g.) in chlorobenzene (3,500 cc.) is added concentrated sulphuric acid (d = 1.83) (16 cc.), representing 0.095 mol per mol of ureidoacetic acid. The water formed in the reaction is removed by azeotropic distillation. After 45 minutes' distillation, a limpid solution is obtained. After cooling to about 15° C, the precipitate formed is filtered off and washed on the filter with ethanol (500 cc.) at 10° C. After drying, 3-(3,5-dichlorophenyl)-hydantoin (724 g.) melting at 199° C is obtained. Yield: 95.4%.

Herkunft & Nachweise