3-(2-formyl-4,5,6,7-tetrahydro-1H-indol-3-yl)propionic acid → 3-{2-[6-(4-Methoxyphenyl)-2-oxo-1,2-dihydroindol-3-ylidenemethyl]-4,5,6,7-tetrahydro-1H-indol-3-yl}-propionic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of 103 mg 6-(4-methoxyphenyl)-2-oxindole, 95 mg 3-(2-formyl-4,5,6,7-tetrahydro-1H-indol-3-yl)-propionic acid and piperidine (3 drops) in ethanol (2 mL) was heated to 90° C. in a sealed tube and held there for 4 hrs. The reaction mixture was concentrated and acidified with 6 N hydrochloric acid. Ethyl acetate was added upon which a solid precipitated from the aqueous layer. The precipitate was collected by filtration, and washed with water and hexane to give 57 mg of 3-{2-[6-(4-Methoxyphenyl)-2-oxo-1,2-dihydroindol-3-ylidenemethyl]-4,5,6,7-tetrahydro-1H-indol-3-yl}-propionic acid as a brown solid (30%).

Provenance & Evidence