Topochemical photoreaction of self-assembled styryldicyanopyrazine dyes and their solid state spectral properties

The selective topochemical photoreaction of styryldicyanopyrazine dyes was studied, and showed an anti head-to-tail type cyclobutane ring. Substituent effects were correlated with the self-assembling characteristics of the reactants. The solid state photoreactions were explained in terms of the specific crystal lattice packing of the molecules and their dynamic performance in the crystal structures with the aid of their X-ray crystal analyses. Absorption and fluorescence spectral properties in the solid state were evaluated by the self-assembling characteristics and the intermolecular PI¯pi interactions in the solid state.