Fully Bridged Triphenylamines Comprising Five‐ and Seven‐Membered Rings

Abstract

A family of fully bridged triphenylamines with embedded 5‐ and 7‐membered rings is presented. The compounds are potent electron donors capable to undergo donor/acceptor interactions with strong cyano‐based acceptors both in the solid state and solution. These interactions were evaluated by IR and UV/vis spectroscopy as well as X‐ray crystallography. The vinylene‐bridged compound was oxidized to the corresponding 1,2‐diketone which readily underwent acid‐catalyzed condensation with selected 1,2‐phenylenediamines. The resulting π‐extended quinoxaline derivatives represent valuable building blocks for the development of functional chromophores upon appropriate functionalization.

Impact of Connectivity on the Electronic Structure of N-Heterotriangulenes

“…The HREELS experiments were performed under ultrahigh vacuum conditions at a sample temperature of around 90 K. The Au(111) single crystal was prepared by standard procedure of Ar + sputtering and annealing. The N-HTAs were synthesized according to the procedures reported in ref . They were deposited from an effusion cell held at 373 K for N-HTA 550 and at 393 K for N-HTA 557 onto the Au(111) sample held at 200 K. The coverage was determined by temperature-programmed desorption measurements (see Supporting Information).…”

“…N-heterotriangulenes (N-HTA, see Figure ), in which the originally propeller-shaped triphenylamine unit is locked into a planar configuration via bridging with appropriate molecular moieties (e.g., carbonyl or dimethylmethylene), represent a class of functional molecules with high potential for optoelectronic materials. − Using structural variation (N-HTA 550 vs 556 vs 557) or substitution patterns opens the opportunity for fine-tuning the electronic properties. ,, …”

“…8−12 Using structural variation (N-HTA 550 vs 556 vs 557) or substitution patterns opens the opportunity for fine-tuning the electronic properties. 9,13,14 The molecular orientation at the interface to an electrode as well as within a molecular film (film morphology) generally plays a central role for device performance, because it strongly influences the electronic properties such as energy level alignment and charge transport properties. 15−28 High-resolution electron energy loss spectroscopy (HREELS) facilitates the analysis of both adsorption orientation and electronic properties of molecules on (semi)conducting surfaces and within thin films.…”

Pyrene-bridged acenaphthenes: synthesis and properties of a diacenaphtho[1,2-e:1′,2′-l]pyrene and its symmetrical nitrogen analogue

“…in NMP at 150 °C led to the desired products, while no conversion of the starting material was observed for other conditions. 22 Products 3a and 3b were isolated in 51 and 56% yields, respectively. To our surprise, annulation of the naphthalene units proceeded at the K-region of pyrene by formation of a five-membered ring, while six-membered ring formation by CH-activation at the peri-position was not observed.…”

Tweaking the Optoelectronic Properties of S‐Doped Polycyclic Aromatic Hydrocarbons by Chemical Oxidation

“…Replacing the carbon atoms with isostructural atoms at given positions is a functionalization strategy to tailor the chemical, optoelectronic, and self-assembly properties of molecular and macromolecular polycyclic aromatic hydrocarbons (PAHs). [1][2][3] While B, [4][5][6][7] N [8][9][10] and P [11][12][13][14][15] heteroatoms can replace both the core and peripheral C(sp2) atoms, the use of chalcogen atoms is fundamentally restricted to the doping of the peripheries. Noticeable examples include O-, [16] S-, [17][18][19] Se- [20][21][22] and Tedoped [23,24] structures.…”