Solid-state valence tautomeric octahedral {Co II [(BQ-N-Cat)] 2 } 0 complex formation via ligand-centered phenolic C-O bond breaking and Co-O bond making.

Ligand H4 LO(AP/AP) underwent ligand-centered C-O bond cleavage during a complexation reaction with Co(ii)-salt. The thus formed octahedral {CoII [(BQ-N-Cat)]2 }0 complex showed valence tautomerization in the solid state. While the process was triggered by the presence of lattice solvent, the nature of the solvent molecule has less effect on the process.