Pyrazinacenes

Synthesis of pyrazinacenes Hepp and Fischer first prepared 5,14-dihydro-5,7,12,14-tetraazapentacene 18 by direct condensation of 2,3-diaminophenazine hydrochloride 16 with o-Phenylenediamine 17. Wudl and co-workers developed a strategy for the synthesis of. -substituted zwitterionic tetraazapentacenes. The preparation involved a double nucleophiUc aromatic substitution of 1,5-difluoro-... 

Most of the known N-heteropentacenes contain pyrazine and/or its reduced form dihydropyrazine in their polycychc backbones and are commonly referred to as pyrazinacenes (Figure 9.2). These molecules have a history of more than a... 

Pyrazinacenes are nitrogen-substituted analogs of the acenes [16], for example, pentacene [22], which is a well-studied p-type semiconductor used in organic electronic devices. Pyrazinacenes, on the other hand, may be complementary to pentacene in that they can offer n-type semiconductor behavior by a very similar... 

Tautomerism in Linear Reduced Fused Oligo1,4-pyrazines (Pyrazinacenes) I 219... 

Figure 9.16 Chemical structure of decaazapyrazinacene, 1, and other examples of pyrazinacenes.

This observed tautomerism could influence the physical properties of these compounds. For instance, semiconductivities of the different isomers would be likely affected while proton mobility along the pyrazinacene backbone should confer interesting materials properties for proton conduction applications (e.g., in fuel cells) of these compounds. 

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