Photophysical, Electrochemical, and Electrogenerated Chemiluminescent Properties of 9,10-Dimethyl-7,12-diphenylbenzo[k]fluoranthene and 9,10-Dimethylsulfone-7,12-diphenylbenzo[k]fluoranthene

Abstract

A newly synthesized light emitting compound 9,10-dimethylsulfone-7,12-diphenylbenzo[k]fluoranthene (DSDPBF) and its synthetic intermediate 9, 10-dimethyl-7,12-diphenylbenzo[k]fluoranthene (DMDPBF) were studied to evaluate how the addition of weak electron donating methyl groups and the subsequent addition of an electron withdrawing sulfone group affect the photophysical and electrochemical properties as well as the rate of radical cation coupling of the parent compound, 7,12-diphenylbenzo[k]fluoranthene (DPBF). Although the photochemical and electrochemical properties of DSDPBF were more similar to the unsubstituted DPBF than to the DMDPBF, there was a substantial decrease in the quantum efficiency upon addition of the electronrich sulfone group which was not observed upon addition of the methyl groups. On the other hand, the rate of radical cation coupling or dimerization observed upon electrochemical oxidation varied significantly. The addition of the electron donating methyl groups decreased the reactivity of the radical cation resulting in a 40 times slower rate of dimerization than that observed for the unsubstituted benzo[k]fluoranthene, whereas the addition of the electron withdrawing sulfone group to the methyl groups increased the radical cation reactivity resulting in a rate of dimerization that was 3 times faster than the unsubstituted parent compound. As a result, the electrogenerated chemiluminescence emission spectrum obtained from the annihilation reaction between the radical anion and radical cations of DSDPBF was dominated by emission from the dimer at 589 and 621 nm instead of emission from the monomer at ca. 485 nm. † Part of the special issue "Noboru Mataga Festschrift".

Electrochemiluminescent Systems as Devices and Sensors

“…Brighter ECL than their unsubstituted counterparts was also observed for 5,11-diphenyltetracene or 9,10-dimethyl-7,12-diphenylbenzo[k]fluoranthene. 125 Alkyl or aryl functionalization tends in formation of more stable radical cations that results brighter ECL emission. Due to sterical effects the functionalization may also results in weaker intermolecular interactions between R À and R þ that marginalizes the formation of weakly emissive excimer 1Ã R 2 and 3Ã R 2 states with increasing efficiency of the excited 1Ã R populations.…”

Benzo[k]fluoranthene-based linear acenes for efficient deep blue organic light-emitting devices

“…20 The bluish fluoranthene derivatives have a large spectrum shift between the solid and solution state photoluminescence (PL), possibly because the strongest emission peak is not from the 0-0 transition state, or the effect of strong reabsorption weakens the deep blue emission. In the fluoranthene families, benzo[k]fluoranthene has outstanding deep blue emission characteristics 23,24 + 2] cycloadditions, in which the different substituents can be easily attached to the core by varying the reactants. 23 This feature enables the screening and tuning of the photo-physical properties of these molecules.…”

Synthesis of Novel Fluoranthene-Based Conformationally Constrained α-Amino Acid Derivatives and Polycyclic Aromatics via the Diels–Alder Reaction

“…1 In this regard, fluoranthene-fused sulfones such as 1 act as a light-emitting compound. 2 Moreover, fluoranthene derivatives (Figure 1), such as 2 and 3, 3a and 4 and 5, 3b,c exhibit interesting photophysical and electrochemical properties, and compounds such as 6 act as fluorescent chemosensors for the detection of explosives such as 2,4,6-trinitrotoluene and picric acid. 3d In view of the interesting photophysical and electrochemical properties of various fluoranthene-fused derivatives, strategies for their syntheses are of great interest.…”

“…3d In view of the interesting photophysical and electrochemical properties of various fluoranthene-fused derivatives, strategies for their syntheses are of great interest. [2][3][4] To this end, Fabrizio et al reported the synthesis of fluoranthene-fused sulfone derivatives such as 9,10-dimethylsulfone-7,12-diphenylbenzo[k]fluoranthene 1 (DSDPBF) 2 employing the Diels-Alder reaction. On the other hand, Pei and co-workers reported the synthesis of fluoranthene-fused imide derivatives 3b,c using the Diels-Alder reaction and decarbonylation as key steps.…”

“…As a part of our major program for the design of unusual α-amino acid derivatives and polycyclic aromatics, we chose to incorporate the fluoranthene ring as a core structural unit and thus α-amino acid derivatives 7-9 and polycyclic aromatics such as 10-12 became our synthetic targets. Due to various interesting properties of fluoranthene-fused derivatives, [2][3][4] we designed a simple route to these α-amino acid derivatives and polycyclic compounds using the Diels-Alder reaction 5 and alkylation as key steps. Here, we report a simple route to fluoranthene- fused conformationally constrained cyclic α-amino acid derivatives involving aminoindanecarboxylic acid 7 (Aic), 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid 8 (Tic), and aminotetralincarboxylic acid 9 (Atc) derivatives, and polycyclic compounds such as 10-12 ( Figure 2).…”