A Functional Hexaphenylbenzene Library Comprising of One, Three, and Six Peripheral Rylene‐Diimide Substituents

Abstract

Synthesis and characterization of a series of rylene‐diimide substituted hexaphenylbenzenes (HPBs) is presented. The direct connection of the rylene‐diimide units to the HPBs via the imide‐N‐position without any linkers as well as the use of naphthalene‐diimides (NDIs) next to perylene‐diimides (PDIs) is unprecedented. While mono‐substituted products were obtained by imidization reactions with amino‐HPB and the respective rylene‐monoimides, key step for the formation of tri‐ and hexa‐substituted HPBs is the Co‐catalysed cyclotrimerization. Particular emphasis for physic‐chemical characterization was on to the number of NDIs/PDIs per HPB and the overall substitution patterns. Lastly, Scholl oxidation conditions were applied to all HPB systems to generate the corresponding hexa‐peri‐hexabenzocoronenes (HBCs). Importantly, the efficiency of the transformation strongly depends on the number of NDIs/PDIs. While three rylene‐diimide units already hinder the Scholl reaction, the successful synthesis of mono‐substituted HBCs is possible.

Helically and Linearly Fused Rylenediimide‐Hexabenzocoronenes

“…The synthesis started with a condensation reaction of the naphthalene‐monoimide 2 [8a] ( n =1) as well as the perylene‐monoimide 3 [8a] ( n =2) with diamino‐bromobenzene 1 (Scheme 1). Already during this reaction, two constitutional isomers are formed in each case, the 4‐Br‐1,2‐ryleneimidebenzimidazole 4 and 5 as well as 5‐Br‐1,2‐ryleneimidebenzimidazole 6 and 7 .…”

How great is the stabilization of crowded polyphenylbiphenyls by London dispersion?

“…hexaphenylbenzene, rubrene) are archetypes for many structures with impact in organic electronics and nanochemistry. [10][11][12][13] Decaphenylbiphenyl was first synthesized in 1965, 1 and reveals itself as an atypical member of the family of perphenyl arenes. To all appearances, decaphenylbiphenyl 1 (1, eqn (1), Table 1) is a strained molecule.…”

“…hexaphenylbenzene, rubrene) are archetypes for many structures with impact in organic electronics and nanochemistry. 10–13…”

π‐Extended Hexapyrrolylbenzenes: Exploring Charge‐Transfer Phenomena in Donor‐Acceptor Propellers

“…To control their donor‐acceptor properties, these compounds were appropriately functionalized by introduction of, for example, secondary amine, azine, aryl borane, or dicyanovinylene groups [20,21,26,29] . Compounds based on the hexaphenylbenzene core are most often obtained using either cyclotrimerization of diarylacetylenes [30,31] or Diels‐Alder cycloaddition of diarylacetylenes to cyclopentadienone derivatives [32,33] . These approaches have limited usefulness in the synthesis of unsymmetrically substituted hexaarylbenzenes, because they typically generate isomeric mixtures that can be difficult to separate, creating a need for alternative synthetic strategies [34,35] …”