Diphenylamine → Acetic Anhydride

Participants

Reaction Steps

Following a procedure similar to that described in Example 3 but employing 1.6 g. of an isomer mixture comprising 3-[(1-ethyl-2-methyl-3-indolyl)carbonyl]-4-pyridinecarboxylic acid and 4-[(1-ethyl-2-methyl-3-indolyl)carbonyl]-3-pyridinecarboxylic acid, 0.9 g. of diphenylamine, 0.5 ml. of pyridine and 6 ml. of acetic anhydride there was obtained 1-(1-ethyl-2-methyl-3-indolyl)-1-(diphenylamino)furo[3,4-c]pyridine-3(1H)-one as a viscous oil. A toluene solution of the product contacted with acidic clay or phenolic resin developed an orange image.

Provenance & Evidence