Synthesis, characterization, and spectroscopic properties of 2-(3,5,6-trichloro-1,4-benzoquinon-2-yl)-neo-fused hexaphyrin

In this work, a novel compound 2-(3,5,6-trichloro-1,4-benzoquinon-2-yl)-neo-fused hexaphyrin has been prepared from tetrachloroquinone and neo-fused hexaphyrin through a substitution reaction. The chemical structure of the compound has been characterized by nuclear magnetic resonance (NMR), high-resolution mass spectrum, UV–Vis spectrum, and X-ray diffraction. The crystal structure reveals that the quinonyl unit is almost coplanar with the adjacent N-confused pyrrole unit. Because of the cooperative effect of extended conjugation and the intramolecular charge transfer effect related to the strong electron-withdrawing character of the quinonyl unit, the absorption of 2 is dramatically extended to ca. 1280 nm.