Potassium 3-cyano-4-(dicyanomethylene)-5-oxo-4,5-dihydro-1H-pyrrol-2-olate

Abstract

The crystal structure of the title potassium salt, K(+).C(8)HN(4)O(2)(-), of the organic anion 3-cyano-4-(dicyanomethylene)-5-oxo-4,5-dihydro-1H-pyrrol-2-olate shows that the dicyanomethylene moiety is able to accept an electron in the same way as does tetracyanoethylene, to yield the novel product. The organic anion is nearly planar, with deviations caused by steric crowding among the exocyclic cyano groups. The K(+) cations lie within tricapped trigonal prisms that stack to form channels. The three-dimensional structure is completed by the formation of hydrogen-bonded chains by the anions.