Generation and characterization of highly strained dibenzotetrakisdehydro[12]annulene

We report here the generation of tetrakisdehydro12]annulene possessing a highly deformed triyne component from the 4.3.2]propellatriene-annelated precursor by its photolysis extruding indan and the characterization of the highly reactive annulene by chemical and spectroscopic methods. In addition to the chemical evidence for the formation of the title compound in solution such as interception as a Diels-Alder adduct, we succeeded in its characterization by UV-vis and FTIR spectra in an argon matrix at 20 K. The experimental IR spectrum agreed well with the theoretical one calculated by the DFT method.