Twisted Polycyclic Aromatic Hydrocarbons. Structural Studies of Protic and Deuteriated 1,2,3,4-Tetraphenyltriphenylenes

Article abstract of DOI:10.1021/jo00243a016

An X-ray crystallographic study of 1,2,3,4-tetraphenyltriphenylene shows that the polycyclic nucleus of this molecule is substantially twisted due to severe nonbonded interactions between the triphenylene hydrogen atoms and the proximal carbons of the 1- and 4-phenyl groups.The two independent molecules in the crystallographic unit cell exhibit twists of 28.1 deg and 30.9 deg, slightly less than the 33 deg twist predicted by MM2(85). 1,2,3,4-Tetraphenyl<5,6,7,8,9,10,11,12-2H8>triphenylene was prepared to determine if the twist angle would be altered by deuteriumsubstitution, and it was found that the X-ray structures of the deuteriated and protic molecules did not differ significantly.