1,3-Benzenediamine, N1,N1,N3,N3-tetramethyl- → 3-[2,4-Bis(dimethylamino)phenyl]-3-(1-ethyl-2-methyl-3-indolyl)-6-nitrophthalide

Participants

Reaction Conditions

Reaction Steps

A mixture of 3.68 g (0.01 mole) of 2-[(1-ethyl-2-methyl3-indolyl)carbonyl]-5-nitrobenzoic acid, prepared as described in part A above, and 2.0 g (0.012 mole) of N,N,N',N'-tetramethyl-m-phenylenediamine in 10.0 ml of acetic anhydride was heated at 90° C. for one hour and then allowed to cool to 25° C. The solid which separated was collected by filtration, washed with diethylether and dried to obtain 3.8 g of 3-[2,4-bis(dimethylamino)phenyl]-3(1-ethyl-2-methyl-3-indolyl)-6-nitrophthalide (Formula III: R°=R1 =R3 =Y1 =H; R2 =NO2 ; R=R5 =CH3 ; R4 =N(CH3)2 ; R6 =CH2CH3) as an orange solid which melted over the range 185°-187° C. The nuclear magnetic resonance spectrum was in accord with the assigned structure. A benzene solution of this product developed a black-purple color when spotted on silica gel.

Provenance & Evidence