Quinonoid zwitterion

The benzene derivate 1,3-dihydroxy-4,6-diaminobenzene is easily oxidized by air in water or methanol to the quinonoid.

In 2002 the compound was found to be more stable and to exist as the zwitterion after a proton transfer.

[1] Evidence for this structure is based on nuclear magnetic resonance spectroscopy and x-ray crystallography.

The positive charge is delocalized between the amino groups over four bonds involving six pi electrons.

The negative charge is spread likewise between the oxygen atoms.