TY - DATA T1 - The Structure of Hexabenzotriphenylene and the Problem of Overcrowded “D3h” Polycyclic Aromatic Compounds PY - 1999/01/14 AU - Lisa Barnett AU - Douglas M. Ho AU - Kim K. Baldridge AU - Robert A. Pascal UR - https://acs.figshare.com/articles/dataset/The_Structure_of_Hexabenzotriphenylene_and_the_Problem_of_Overcrowded_i_D_i_sub_3_sub_i_sub_h_sub_i_Polycyclic_Aromatic_Compounds/3673008 DO - 10.1021/ja983471i.s001 L4 - https://ndownloader.figshare.com/files/5762769 KW - origin KW - Compound 1 KW - C 2 KW - compound KW - Aromatic KW - phenanthro KW - triphenylene KW - D 3 h KW - Hexabenzotriphenylene KW - picene KW - Polycyclic KW - Overcrowded KW - perfluoro KW - Computational studies KW - vacuum pyrolysis KW - anhydride KW - phenanthrene KW - conformation KW - polycyclic KW - adequacy KW - dibenzo KW - propeller KW - Problem KW - method KW - D 3 KW - contrast KW - perchlorotriphenylene KW - preference N2 - Hexabenzotriphenylene (1, dibenzo[f,j]phenanthro[9,10-s]picene) has been prepared in 5% yield by vacuum pyrolysis of phenanthrene-9,10-dicarboxylic anhydride, and its X-ray structure has been determined. Compound 1 is a strongly twisted, D3-symmetric molecular propeller, in contrast to other highly substituted triphenylenes (perfluoro- and perchlorotriphenylene) which adopt C2-symmetric conformations. Computational studies of these and other overcrowded, nominally D3h-symmetric, polycyclic aromatic compounds are reported, and the origins of their conformational preferences and the adequacy of various computational methods for treating these compounds are discussed. ER -