A concise method to prepare linear 2,3-diazaoligoacene derivatives

In this Letter, we demonstrate that linear 2,3-diazanaphthalene (1), 2,3-diazaanthracene (2), and 2,3-diazatetracene (3) can be easily prepared through [4+2] cycloaddition reaction between 3,6-diphenyl-1,2,4,5-tetrazine as the diene and arynes as dienophiles, generated in situ from ortho-aminoarylcarboxylic acids. The physical properties and crystal packing of the prepared compounds 1-3 were fully investigated. In addition, the experimental data (e.g., band gap and band position) are further confirmed by theoretical studies.