5,12‐Diaminotetracenes: The Impact of Orbital Interactions between the Acene π System and Amino Groups on Their Electronic States

Abstract

5,12-Diamino-substituted tetracenesw ithv arious N-substituents have been prepared, and their molecular structural changes upon oxidation have been evaluated in association with their electronic structures. The N-substituents influence both the electronic and molecular structures of the oxidized specieso f5 ,12-diaminotetracenes. The tetracene moiety of 5,12-bis(N,N-dianisylamino)tetracene retained its planarity during the courseo ft wo successive one-electron oxidations, whereas 5,12-bis(N,N-dimethylamino)tetracene and 5,12-bis(N-anisyl-N-methylamino)tetracene underwent substantial structural changes into butterfly like struc-tures throughasimultaneous two-electron oxidation process. The molecular structures in the oxidized states were closely relatedt ot he nature of the highest occupiedo rbitals, which were characterized by the extento fm ixingb etweent he fragment orbitals for the teracene moiety and the substituted amino groups in 5,12-diaminotetracenes. As a consequence, the present work revealed that the extent of foldingd eformation of the acene moiety in the oxidized diaminoacenes could be fine-tuned by varying the N-substituents.[a] Dr.M.U Scheme1.Synthesis of diaminotetracenes 1-3.DABCO = 1,4-diazabicyclo[2.2.2]octane, dba = dibenzylideneacetone.