Of higher acenes

There has been little work on the functionalization of higher acenes, owing to the poor stability and very low solubility of the non-benzannelated derivatives. A poorly refined crystal structure of unsubstituted hexacene has been reported (without atomic coordinates), implying that it too arranges in a herringbone motif analogous to the lower acenes [87]. 

The only transistor examples of higher-acenes based semiconductors are molecules containing an electron-rich acene unit and an electron-poor quinoid unit (4a-4c).[79] The packing influenced by this structure is such that acene units stack over... 

Beyond Pentacenes Synthesis and Properties of Higher Acenes... 

The enormous interest in pentacene has naturally led to the question of whether larger acenes could have even more favorable properties for materials applications. This has led to a revival of the chemistry of higher acenes in the last decade. 

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