Reaction of 1, 1′, 2, 2′-Tetrakis (phenylamino) Ethane with Glyoxal; Synthesis of N2, N3, N7, N8, 1, 4, 5, 6, 9, 10 -Decaphenyltetradecahydro - dipyrazino [2, 3-b: 2, 3-e] Pyrazine-2, 3, 7, 8 -Tetraamine and 5, 6 -bis (ethoxy) -N2, N3, 1, 4 -Tetraphenylhexahydro -2, 3- Pyrazinediamine

Abstract

<em>Compound N², N³, N⁷, N⁸, 1, 4, 5, 6, 9, 10-decaphenyltetradecahydrodipyrazino [2, 3-b: 2, 3-e] pyrazine-2, 3, 7, 8-tetraamine (4) was prepared by condensation of 1, 1′, 2, 2′-tetrakis (phenylamino) ethane (1d) and glyoxal in EtOH or i-PrOH. Also, reaction of 1d with glyoxal in equimolare in EtOH resulted 5,6-bis (ethoxy)-N², N³, 1, 4-tetraphenylhexahydro-2, 3-pyrazinediamine (5). The natures of products are sensitive to acidity, temperature and solvent. In acidic media, 4 and 5 are unstable and degraded to diimine 6.</em> <em> </em>