PHENACENES - A FAMILY OF GRAPHITE RIBBONS .1. SYNTHESES OF SOME [7]PHENACENES BY STILBENE-LIKE PHOTOCYCLIZATIONS

The largest previously reported phenacene, the name we propose for the family of polycyclic aromatic compounds having fused benzene rings in an extended phenanthrene-like structural motif, contains only six rin gs ([6]phenacene). We have employed stilbene-like photocyclizations to synthesize the unsubstituted [7]phenacene, an extremely insoluble com pound, as well as 2,13-di-n-pentyl[7]phenacene and 2,13-di-tert-buty[7 ]phenacene, two alkyl-substituted derivatives with greatly improved so lubilities. Copyright (C) 1996 Published by Elsevier Science Ltd