Kinetically, both heat and the presence of additional K + cations can be shown to be necessary for the transformation to occur. C=O/C=C conjugation within the [C4O4] 4-unit (manifested through resonance structures featuring a central C(2)-C(2') single bond) presumably lowers the barrier to rotation about the central C=C double bond, and allows mechanistically for the anti-to-syn isomerization process. .