Dimethylformamide → HCID 22827913, compound

Participants

Reaction Steps

20 ml (0.26 mole) of dimethylformamide are added dropwise to 120 g (0.9 mole) of anhydrous aluminum chloride in the course of a few minutes, while stirring, a highly exothermic reaction taking place. A mixture of 11.8 g (0.089 mole) of indolin-2-one and 11.3 g (0.09 mole) of cyclobutanedicarboxylic anhydride is then added a little at a time at 140° C., after which stirring is continued for a further 10 minutes at this temperature. The melt is then introduced into 0.5 kg of ice. The precipitated solid is filtered off under suction, and the aqueous phase is extracted several times with ethyl acetate. 21.7 g (93.6%) of cis-2-(indolin-2-on-5-oyl)-cyclobutanecarboxylic acid of melting point 211°-212° C. are obtained.

Provenance & Evidence