Pyrrolidine → 4-Chloro-2-(6-chloro-2-oxo-1,2-dihydro-indol-3-ylidenemethyl)-benzoic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

To the mixture of 6-chlorooxindole (1.2 g, 7 mmol) and 4-chloro-2-formyl-benzoic acid methyl ester (1.4 g, 7 mmol) in methanol (10 mL) was added pyrrolidine (490 mg, 7 mmol) dropwise. The mixture was then heated at 70° C. for 3 h. After cooled to 4° C., the mixture was filtered and the precipitate was collected, dried to give a mixture of E/Z-6-chloro-3-(5-chloro-2-hydroxy-benzylidene)-1,3-dihydro-indol-2-one as a bright yellow solid (500 mg).

Provenance & Evidence