Journal of the American Chemical Society, Vol.141, No.26, 10165-10170, 2019
Open-Shell and Antiaromatic Character Induced by the Highly Symmetric Geometry of the Planar Heptalene Structure: Synthesis and Characterization of a Nonalternant Isomer of Bisanthene
A nonbenzenoid hydrocarbon, difluoreno-[1,9,8-alkj:1',9',8'-gfed]heptalene 1, is synthesized. Experimental and theoretical investigations demonstrate that the planar and symmetric heptalene core within 1 effectively induces the antiaromatic and open-shell character. These properties are not shared by bisanthene 2, a benzenoid isomer of 1.