1361119-48-3

Upstream product

• 523-27-3 9,10-Dibromoanthracene 
• 63697-96-1 4-Ethynylbenzaldehyde 
• 18512-55-5 9,10-diethynylanthracene 
• 1122-91-4 4-bromo-benzaldehyde 
• 120-12-7 anthracene 
• 18750-95-3 9,10-bis(trimethylsilyl)ethynylanthracene 

Downstream Products

• 1361119-51-8 9,10-bis(4-formylphenylethynyl)-9,10-dihydro-9,10-epidioxidoanthracene 

Relevant academic research and scientific papers

The relationship between molecular structure and electronic properties in dicyanovinyl substituted acceptor-donor-acceptor chromophores

In this contribution we describe a combined experimental and theoretical study of the relation between the molecular structure and the electronic properties of conjugated donor-acceptor type chromophores for light-harvesting applications. A series of model systems was synthesized where a central anthracene (electron donor) is connected to dicyanovinyl units (electron acceptor) through a π-conjugated spacer. The study of the redox and optical properties of these chromophores and of reference compounds without dicyanovinyl units allows us correlate the electronic properties to the presence of the electron withdrawing groups and the molecular conformation. Comparison with calculated electronic structure shows that the construction of chromophores that consist of electron donating and accepting units does not always follow the simple rules that are generally used in the design of such molecules. The results show a subtle relation between the charge transfer character and the geometry of the molecules. In some cases this leads to significant contribution of charge transfer excitation to the absorption spectra of some chromophores while such contributions are completely absent in others.

Synthesis, photophysical properties, and field-effect characteristics of (ethynylphenyl)benzimidazole-decorated anthracene and perylene bisimide derivatives

A series of anthracene and perylene bisimide derivatives with electron-withdrawing benzimidazole substituents has been designed and prepared. Detailed studies on the electrochemical and photophysical properties as well as the field-effect mobilities of these new compounds were explored. The incorporation of electron-withdrawing benzimidazole groups lowered the LUMO levels in both anthracene and perylene bisimide derivatives compared to those of the parent compounds. Strong emission was observed for all anthracene derivatives, but only weak emission was observed for perylene bisimide derivatives. The anthracene derivatives showed typical p-type semiconducting character, even when the derivatives were substituted with electron-withdrawing benzimidazole groups at the 9- and 10-positions, which apparently does not lower the LUMO levels to transform them into electron-transporting molecules. Perylene bisimide derivatives displayed typical n-channel semiconducting properties with low threshold voltages and electron mobilities of ca. 5.2 × 10-5 cm2 V-1 s-1. Copyright

Why triple bonds protect acenes from oxidation and decomposition

An experimental and computational study on the impact of functional groups on the oxidation stability of higher acenes is presented. We synthesized anthracenes, tetracenes, and pentacenes with various substituents at the periphery, identified their photooxygenation products, and measured the kinetics. Furthermore, the products obtained from thermolysis and the kinetics of the thermolysis are investigated. Density functional theory is applied in order to predict reaction energies, frontier molecular orbital interactions, and radical stabilization energies. The combined results allow us to describe the mechanisms of the oxidations and the subsequent thermolysis. We found that the alkynyl group not only enhances the oxidation stability of acenes but also protects the resulting endoperoxides from thermal decomposition. Additionally, such substituents increase the regioselectivity of the photooxygenation of tetracenes and pentacenes. For the first time, we oxidized alkynylpentacenes by using chemically generated singlet oxygen (1O2) without irradiation and identified a 6,13-endoperoxide as the sole regioisomer. The bimolecular rate constant of this oxidation amounts to only 1 × 10 5 s-1 M-1. This unexpectedly slow reaction is a result of a physical deactivation of 1O2. In contrast to unsubstituted or aryl-substituted acenes, photooxygenation of alkynyl-substituted acenes proceeds most likely by a concerted mechanism, while the thermolysis is well explained by the formation of radical intermediates. Our results should be important for the future design of oxidation stable acene-based semiconductors.

Reversible photooxygenation of alkynylanthracenes: Chemical generation of singlet oxygen under very mild conditions

In the dark and very fast: The generation of singlet oxygen ( 1O2) from endoperoxides, which are readily available by photooxygenation of the corresponding anthracenes, proceeds within minutes in the dark (see scheme), a rate hitherto unknown for other anthracenes or naphthalenes. This provides an efficient chemical source of singlet oxygen under very mild conditions.