Hydrochloric Acid → HCID 86713233, compound

Participants

Reaction Conditions

Reaction Steps

In a 20 mL reaction vessel were placed 88 mg (0.27 mmol) of 6-[2-methoxy-4-(4-pyridylmethoxy)phenyl]hex-5-ene-2,4-dione and 26.4 mg (0.380 mmol) of boron oxide and they were dissolved in 1.76 mL of ethyl acetate. To the mixture under stirring at 70° C., 40 mg (0.27 mmol) of 1H-indole-7-carboxaldehyde and 124 μL (0.54 mmol) of triisopropyl borate were sequentially added. After the mixture was stirred at the same temperature for 1 hour, a solution of 5.4 μL (54 μmol) of piperidine in ethyl acetate (0.27 mL) was added and the mixture was further stirred for 1 hour. To the reaction mixture was added a 1:1 solution (0.8 mL) of 1 N hydrochloric acid and saturated brine at room temperature and the mixture was stirred for 5 minutes to 1 hour (further, the mixture was neutralized with a saturated sodium bicarbonate aqueous solution as needed). The resulting organic phase was directly subjected to purification by silica gel column chromatography (hexane/ethyl acetate or methylene chloride/methanol) to give 43.5 mg (36% yield) of the title compound as a yellow powder.

Provenance & Evidence