Acetic Anhydride → HCID 14149591, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 15.6 g of 2-(2-methyI-4-diethylaminophenyl)carbonylbenzoic acid, 12.5 g of 1-(2-vinyloxyethyl)-2-methylindole, and 50.0 ml of acetic anhydride was maintained at approximately 70° C. for approximately four hours. The resulting solution was cooled to ambient temperature and slowly poured into a mixture of toluene and 5 percent aqueous ammonium hydroxide. The toluene layer was separated, washed successively once each with water and saturated sodium chloride solution and evaporated to dryness. The residue that remained was heated in a 1:1 mixture of isopropyl alcohol:hexane. The liquid was decanted from a gummy residue. The residue was dissolved in 100.0 ml of acetone and the resulting solution was added dropwise to 1500.0 ml of 2 percent aqueous ammonium hydroxide. The solid which precipitated was collected by filtration, washed with water and dried to obtain 18.86 g of 3-[1-(2-vinyloxyethyl)-2-methylindol-3-yl]-3-(2-methyl-4-diethylaminophenyl)phthalide (Formula I: R1 =CH2 =CHOC2H4 ; R1 =R2 =CH3 ; R3 =R4 =C2H5 ; X=Y=H), a tan-colored solid which melted over the range 135°-141° C. Significant infrared maxima appeared at 1760 (C=O;s) and 1120 (C--O;s)cm A toluene solution of the product spotted on an acid clay or a phenolic resin coated paper developed a cyan-colored image.

Provenance & Evidence