Indole-2-carboxaldehyde → 6-chloro-3-(1H-indol-2-ylmethylene)-1,3-dihydroindol-2-one

Participants

Reaction Steps

A mixture of 6-chloro-2-oxindole (41 mg) (commercially available), indole-2-carbaldehyde (42 mg) (prepared according to Synthetic Communications, 1993, 23, 3109) and piperidine (1 drop) in ethanol (3 mL) was held in a sealed tube at 95° C. for 3 hours. The mixture was cooled to room temperature. The solid was collected by vacuum filtration, washed with cold ethanol and dried in vacuum oven to give 62 mg (87% yield) of 6-chloro-3-(1H-indol-2-ylmethylene)-1,3-dihydroindol-2-one as a shiny orange solid.

Provenance & Evidence