2,3-Dichloro-5,6-dicyano-1,4-benzoquinone → 2-(1H-Indol-2-yl)quinoline

Participants

Reaction Conditions

Reaction Steps

The indolyl-tetrahydroquinoline was made according to the established lanthanide triflate catalyzed Kobayashi chemistry (for a leading reference, see Kobayashi, S.; Ishitani, H.; Nagayama, S. Synthesis, 1995, 1195-1202). The tetrahydroquinoline (50.0 mg, 0.102 mmol) was dissolved in 10 mL anhydrous dichloromethane and the solution was cooled to 0° C. under nitrogen atmosphere. 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (47.6 mg, 0.210 mmol) in 2 mL dichloromethane was then added in a drop-wise fashion. The reaction mixture was stirred at 0° C. for additional 30 minutes. The reaction crude was filtered through celite and the solvent was evaporated in vacuo to supply a yellow solid. Further purification by flash column chromatography (alumina basic, CH2Cl2/MeOH=20:1) yielded 27.5 mg of indolyl-quinoline 517.

Provenance & Evidence