Acetic Anhydride → HCID 20268295, compound

Participants

Reaction Steps

In a procedure similar to that described above in part B of this example, 12.28 g (0.04 mole) of 2-[(1-ethyl-2-methyl-3-indolyl)carbonyl]benzoic acid, prepared as described in part A above, 8.57 g (0.05 mole) of N,N,N',N'-tetramethyl-m-phenylenediamine and 6.0 ml of acetic anhydride were interacted with stirring at room temperature overnight. The reaction mixture was then diluted with 13.0 ml of ethanol and the precipitate which separated was filtered and washed with 6.0 ml of ethanol. The filter cake was then reslurried in 30 ml of methanol, filtered and washed successively with methanol and diethylether. The material was dried in vacuo to obtain 15.8 g of 3-[2,4-bis(dimethylamino)phenyl]-3-(1-ethyl-2-methyl-3-indolyl)phthalide (Formula III: R0 =R1 =R2 =R3 =Y1 =H; R=R5 =CH3 ; R4 =N(CH3)2 ; R6 =CH2CH3), a white crystalline solid which melted at 218°-222° C. The infrared spectrum was consistent with the structure. A benzene solution of the above product developed an intense grape-red color when streaked on a phenolic resin coated paper.

Provenance & Evidence