The spectral and chemical properties show the influence of the central [4n] ring, leading to considerable interest in the system in terms of its degree of lessened aromaticity.
[12] The biphenylene structure can also be understood as a dimer of the reactive intermediate benzyne, which in fact serves as a major synthetic route, by heating the benzenediazonium-2-carboxylate zwitterion prepared from 2-aminobenzoic acid.
Even a complete 2-dimensional carbon sheet with biphenylene-like subunits has been proposed[20] and was in-depth investigated by theoretical means, finding a technologically relevant direct band gap of ca.
[21][22][23] Researchers synthesized a biphenylene sheet consisting of sp2-hybridized carbon atoms that formed four-, six-, and eight-membered rings on a smooth gold surface.
A bottom-up two-step interpolymer dehydrofluorination of an adsorbed halogenated terphenyl molecule polymerization yielded ultraflat four- and eight-membered rings.