Triphenylpyrazine: methyl substitution to achieve deep blue AIE emitters

Based on our deep comprehension of the unique excited state decay process of tetraphenylpyrazine derivatives, triphenylpyrazine-3-carbazole (TrPP-3C) was designed by replacing the phenyl group with a methyl group at the 3-position of pyrazine.

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Absorption, fluorescence, Raman spectroscopic and density functional theoretical studies on the singlet and triplet excited state decay of 3-amino-5-mercapto-1,2,4-triazole

RSC Advances ◽

10.1039/d0ra01628d ◽

2020 ◽

Vol 10 (23) ◽

pp. 13442-13450

Author(s):

Aimin Duan ◽

Suosuo An ◽

Jiadan Xue ◽

Xuming Zheng ◽

Yanying Zhao

Keyword(s):

Biological Sciences ◽

Excited State ◽

Heterocyclic Compounds ◽

Density Functional ◽

Decay Process ◽

Theoretical Studies ◽

Triplet Excited State ◽

Raman Spectroscopic ◽

State Decay

The excited state decay process of N-heterocyclic compounds is attracting increasing attention due to their fundamental applications in pharmaceutical and biological sciences.

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Tetraphenylpyrazine Based AIE Luminogens: Unique Excited State Decay and Its Application in Deep‐Blue Light‐Emitting Diodes

Advanced Optical Materials ◽

10.1002/adom.201801673 ◽

2019 ◽

Vol 7 (6) ◽

pp. 1801673 ◽

Cited By ~ 12

Author(s):

Lingxiang Pan ◽

Haozhong Wu ◽

Junkai Liu ◽

Kaiqi Xue ◽

Wenwen Luo ◽

...

Keyword(s):

Excited State ◽

Blue Light ◽

Light Emitting Diodes ◽

Light Emitting ◽

State Decay ◽

Deep Blue

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Rotational Coherence Spectroscopy and Excited-State Dynamics of Tolane and its Van Der Waals Complexes with Argon and Nitrogen

Laser Chemistry ◽

10.1155/1994/60684 ◽

1994 ◽

Vol 14 (1-3) ◽

pp. 45-59 ◽

Cited By ~ 4

Author(s):

Shane M. Ohline ◽

Joann Romascan ◽

Peter M. Felker

Keyword(s):

Excited State ◽

Van Der Waals ◽

Decay Process ◽

Van Der Waals Complexes ◽

Planar Geometry ◽

Small Species ◽

Excited State Dynamics ◽

State Decay ◽

Coherence Spectroscopy ◽

Vibronic States

We report the results of rotational coherence spectroscopy on tolane, tolane–Ar, and tolane–N2. The results on tolane are consistent with a planar geometry for the species. They also provide information about the symmetries of excited vibronic states in the species. The results on the van der Waals complexes provide significant experimental constraints on where the small species bind to tolane. In addition, we report the observation of a rapid excited-state decay process in the complexes and discuss the possible nature of this process.

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Novel Carbazole-based Multifunctional Materials with Hybridized Local and Charge-Transfer Excited State Acting as Deep Blue Emitters and Phosphorescent Hosts for Highly Efficient Organic Light-Emitting Diodes

Journal of Materials Chemistry C ◽

10.1039/d1tc00494h ◽

2021 ◽

Author(s):

Haitao Zhou ◽

Mengna Yin ◽

Zhenhong Zhao ◽

Yanqin Miao ◽

Xin Jin ◽

...

Keyword(s):

Excited State ◽

Charge Transfer ◽

Light Emitting Diodes ◽

Organic Light Emitting Diodes ◽

Multifunctional Materials ◽

Light Emitting ◽

Highly Efficient ◽

Deep Blue ◽

Organic Light ◽

Blue Emitters

In this work, two carbazole- and benzo[d]oxazole-based novel multifunctional materials with hybridized local and charge-transfer (HLCT) characteristic, namely OCI and OCT, which could act as deep-blue fluorophors and phosphorescent hosts,...

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The photocycloaddition of dibenzoylmethanatoboron difluoride (DBMBF2) with conjugated enones and en-esters

Canadian Journal of Chemistry ◽

10.1139/v93-113 ◽

1993 ◽

Vol 71 (6) ◽

pp. 846-854 ◽

Cited By ~ 13

Author(s):

Yuan L. Chow ◽

Shi-Sen Wang ◽

Xian-En Cheng

Keyword(s):

Excited State ◽

Charge Transfer ◽

Ring Opening ◽

Electron Donors ◽

Head Orientation ◽

Singlet Excited State ◽

Methyl Substitution ◽

Unsaturated Ketones ◽

Dibenzoylmethanatoboron Difluoride

Dibenzoylmethanatoboron difluoride (DBMBF2), the BF2 complex of dibenzoylmethane, reacted from its singlet excited state with α,β-unsaturated ketones and esters to give 1,5-diketones by a [2+2] cycloaddition and ring-opening sequence in an analogous pathway to that observed in the photocycloaddition to olefins and dienes. The present photoreaction is unexpected since conjugated enones and en-esters are poor electron donors to comply with the previously proposed charge transfer requirement in DBMBF2 photoreactions. The photocycloaddition to these substrates was highly regioselective and stereoselective, giving the head-to-head orientation, which could be enhanced by α-methyl substitution; β-methyl substitution increased the alternate head-to-tail orientation. The photolysis of a mixture of DBMBF2 and a cyclic enone also caused the latter to dimerize to give head-to-head and head-to-tail dimers in significant yields. These photodimerizations were apparently caused by DBMBF2 sensitization. The mechanism of the sensitization is discussed.

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The Photochemical Reactivity of Some Benzoylthiophenes. III. The Effect of an Adjacent Methyl Group on the Excited State Reactivity of 2-Benzoylthiophene

Canadian Journal of Chemistry ◽

10.1139/v75-001 ◽

1975 ◽

Vol 53 (1) ◽

pp. 1-11 ◽

Cited By ~ 16

Author(s):

D. R. Arnold ◽

B. M. Clarke Jr.

Keyword(s):

Excited State ◽

Carbonyl Group ◽

Emission Spectra ◽

Ultraviolet Absorption ◽

Photochemical Reactivity ◽

Methyl Group ◽

Partial Energy ◽

Phosphorescence Emission ◽

Π State

The ultraviolet absorption and phosphorescence emission spectra of 2-(2-methylbenzoyl) thiophene (1), 2-benzoyl-3-methylthiophene (2), 2-benzoyl-4-methylthiophene (3), and 2-benzoyl-5-methylthiophene (4) are reported and analyzed. Partial energy diagrams are constructed. The lowest triplet is assigned as a π,π* state of the 2-thienoyl chromophore in every case. Photocycloaddition of isobutylene to the carbonyl group was observed with 1 and 2. The oxetanes are thermally unstable; olefins 1-(2-thienyl)-1-(2-methylphenyl)-2-methylpropene (from 1) and 1-phenyl-1-(2-(3-methylthienyl))-2-methylpropene (from 2) were formed and characterized. Irradiation of 1 and 2 in O-deuteromethanol did not lead to incorporation of deuterium; no reaction was observed. These results are discussed in terms of the existing generalizations potentially useful for predicting photochemical reactivity.

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