Development of solid-state emissive o-carboranes and theoretical investigation of the mechanism of the aggregation-induced emission behaviors of organoboron “element-blocks”

2017 ◽  
Vol 196 ◽  
pp. 31-42 ◽  
Author(s):  
Kazuo Tanaka ◽  
Kenta Nishino ◽  
Shunichiro Ito ◽  
Honami Yamane ◽  
Kazumasa Suenaga ◽  
...  
Keyword(s):  
Excited State ◽  
Conformational Changes ◽  
Functional Group ◽  
Theoretical Calculations ◽  
Luminescent Properties ◽  
Ring Structure ◽  
Aggregation Induced Emission ◽  
Intramolecular Mobility ◽  
Fused Ring ◽  
Potential Strategy

This paper presents the aggregation-induced emission (AIE) properties of o-carborane derivatives and proposes a potential strategy for constructing AIE-active organoboron complexes via the enhancement of freedom of intramolecular mobility. Initially, the optical properties of o-carborane derivatives with or without the fused ring structure at the C–C bond in o-carborane in which elongation should be induced by photo-excitation according to theoretical calculations were compared. Accordingly, it was shown that large mobility at the C–C bond in o-carborane should be responsible for the annihilation of emission in solution, leading to the AIE property. From this result, it was presumed that by enhancing the freedom of intramolecular mobility in conventional luminescent organoboron complexes, the deactivation of the excited state in solution and emission recovery in the aggregate can be induced. Based on this idea, we have performed several studies and introduce two representative results. Firstly, the decrease in luminescent properties of boron dipyrromethene (BODIPY) in solution by introducing a movable functional group is explained. Next, the AIE behaviors of boron ketoiminates and the potential mechanism concerning conformational changes for the deactivation of the excited state in the solution state are illustrated. It is proposed that enhancement of the freedom of mobility in the excited state of luminescent organoboron complexes could be a potential strategy for realizing AIE behaviors.

Conformational changes in hydroxyl functional group upon hydration: the case study of Endo Fenchol

2020 ◽  
Author(s):  
Elias M Neeman ◽  
Thérèse Huet
Keyword(s):  
Fourier Transform ◽  
Gas Phase ◽  
Conformational Changes ◽  
Functional Group ◽  
Theoretical Calculations ◽  
Supersonic Jet ◽  
Microwave Spectrometer ◽  
Supersonic Jet Expansion ◽  
Hydroxyl Functional Group

The hydration of endo-fenchol has been studied in the gas phase using a combination of Fourier transform microwave spectrometer coupled to a supersonic jet expansion and theoretical calculations in the...

The Pyrolytic Rearrangement of 1-Alkynoyl-3-methylpyrazoles: Synthesis of Pyrazolo[1,5-a]pyridin-5-ols and Related Compounds

1994 ◽  
Vol 47 (6) ◽  
pp. 991 ◽  
Author(s):  
RFC Brown ◽  
FW Eastwood ◽  
GD Fallon ◽  
SC Lee ◽  
RP Mcgeary
Keyword(s):  
Carbon Chain ◽  
Ring Structure ◽  
High Yield ◽  
Methyl Group ◽  
X Ray ◽  
X Ray Crystallography ◽  
Flash Vacuum Pyrolysis ◽  
Vacuum Pyrolysis ◽  
Fused Ring ◽  
Related Compounds

Flash vacuum pyrolysis of 1-(alkyn-2′-oyl)-3-methylpyrazoles at 650°/0.03 mm forms pyrazolo[1,5-a]pyridin-5-ols, often in high yield, which may bear substituents at C2, C3 or C7. In the absence of a 3-methyl group in the precursor, N-ethynylpyrazoles are formed in low yield. The formation of both types of product is interpreted as involving 3-(N-pyrazolyl)propadienones formed by N1 → N2 migration of the N-alkynoyl group with inversion of the three-carbon chain. The fused-ring structure of 2-methylpyrazolo[1,5-a]pyridin-5-ol (25) was established by X-ray crystallography of the O-benzoyl derivative (27).

Synthesis and Ring Cyclization - Expansion - Contraction Reactions of Some New 2,2-Disubstituted Indan-1,3-diones and Related Compounds

2006 ◽  
Vol 59 (1) ◽  
pp. 59 ◽  
Author(s):  
Craig J. Roxburgh ◽  
Lee Banting
Keyword(s):  
Catalytic Hydrogenation ◽  
Pyridine Ring ◽  
Functional Group ◽  
Chemical Properties ◽  
Ring Expansion ◽  
Ring Structure ◽  
Side Reactions ◽  
The Third ◽  
Ring Expansion Reaction ◽  
Related Compounds

We have found that the hydrochloride of 2-phenyl-2-[2-(2-piperidyl)ethyl]-4,5,6,7-tetrahydroindan-1,3-dione 1 possesses marked analgesic activity (100% inhibition referenced to codeine) and report, as part of an extensive synthetic program, the synthesis of 38 new and structurally related compounds. Selective catalytic hydrogenation of the pyridine ring of 2-phenyl-2-[2-(2-pyridyl)ethyl]-indan-1,3-dione 2 yields the nine-membered nitrogen-containing heterocycle 6 by a novel ring cyclization–expansion reaction. The structural and functional group parameters required for this novel ring-expansion reaction have been extensively and thoroughly investigated through the synthesis of a series of structurally related compounds; principally by modification, substitution, and replacement of the various functionality contained within 2. In addition, we report the synthesis of a series of new 2-methyl-2-(ω-N-phthalimidoalkyl)-indan-1,3-diones 41, 45, and 53, two of which, like the parent 2-phenyl substituted indan-1,3-dione 2, also undergo a novel ring cyclization–expansion reaction to yield eight- and nine-membered nitrogen-containing rings. However, in these cases, further transannular reactions occur to produce the new 5,5- and 5,6-ring-fused nitrogen-containing heterocycles 44, 48 and 51, 52. Hydrazinolysis of the third, 2-methyl-2-(4-N-phthalimidobutyl)-indan-1,3-dione yields the new azepine-containing ring structure 56 by direct cyclization. Furthermore, some interesting and unexpected chemical properties of the final compounds, which include selective and non-selective pyridine-ring hydrogenations and a few unexpected side reactions, are described.

Excited state dynamics for hybridized local and charge transfer state fluorescent emitters with aggregation-induced emission in the solid phase: a QM/MM study

2017 ◽  
Vol 19 (44) ◽  
pp. 29872-29879 ◽  
Author(s):  
Jianzhong Fan ◽  
Lei Cai ◽  
Lili Lin ◽  
Chuan-Kui Wang
Keyword(s):  
Excited State ◽  
Charge Transfer ◽  
Solid Phase ◽  
Charge Transfer State ◽  
Aggregation Induced Emission ◽  
Excited State Dynamics ◽  
Transfer State

Investigation on the excited state dynamics to reveal the AIE and HLCT mechanisms by a QM/MM method.

Capturing and Analyzing the Excited-State Structure of a Cu(I) Phenanthroline Complex by Time-Resolved Diffraction and Theoretical Calculations

2009 ◽  
Vol 131 (18) ◽  
pp. 6566-6573 ◽  
Author(s):  
Ivan I. Vorontsov ◽  
Tim Graber ◽  
Andrey Yu. Kovalevsky ◽  
Irina V. Novozhilova ◽  
Milan Gembicky ◽  
...  
Keyword(s):  
Excited State ◽  
Theoretical Calculations ◽  
State Structure ◽  
Time Resolved ◽  
Phenanthroline Complex

scholarly journals Free Radical Mediated Oxidative Degradation of Carotenes and Xanthophylls

Molecules ◽  
2020 ◽  
Vol 25 (5) ◽  
pp. 1038 ◽  
Author(s):  
Raphael C. Mordi ◽  
Olabisi T. Ademosun ◽  
Christiana O. Ajanaku ◽  
Ifedolapo O. Olanrewaju ◽  
John C. Walton
Keyword(s):  
Excited State ◽  
Free Radical ◽  
Vitamin A ◽  
Molecular Oxygen ◽  
Oxidative Degradation ◽  
Chain Structure ◽  
Ring Structure ◽  
Peroxyl Radicals ◽  
Chemical Structures ◽  
Excited State Quenching

This article reviews the excited-state quenching, pro-vitamin A activity and anticarcinogenicity of carotenes and xanthophylls in relation to their chemical structures. Excited-state quenching improved with the length of the conjugated chain structure. Pro-vitamin A activity was dependent on the presence of at least one beta-ionyl ring structure. The effectiveness of carotenoids as antioxidants depended on their ability to trap peroxyl radicals with production of resonance-stabilized carotenyl radicals. The products identified from oxidations of carotenes and xanthophylls with molecular oxygen and other oxidizing agents are presented. The free radical-mediated mechanisms that have been proposed to account for the different classes of products are reviewed.

scholarly journals Wavelength dependent nonlinear optical response of tetraphenylethene aggregation-induced emission luminogens

2018 ◽  
Vol 2 (12) ◽  
pp. 2263-2271 ◽  
Author(s):  
Jianbo Xiong ◽  
Xinyue Li ◽  
Chunqing Yuan ◽  
Sergey Semin ◽  
Zhaoquan Yao ◽  
...  
Keyword(s):  
Optical Properties ◽  
Nonlinear Optical ◽  
Theoretical Calculations ◽  
Experimental Results ◽  
Nlo Properties ◽  
Aggregation Induced Emission ◽  
Non Linear ◽  
Potential Applications ◽  
Linear Optical Properties ◽  
Linear Optical

Studies of the non-linear optical properties of classical AIEgens are rare, despite their important potential applications in organic composite photonic circuits. Here, we present experimental results, supported by theoretical calculations, of the non-linear optical (NLO) properties of TPE and its halogenated derivates.

scholarly journals Restriction of Conformation Transformation in Excited State: An Aggregation-Induced Emission Building Block Based on Stable Exocyclic C=N Group

iScience ◽  
2020 ◽  
Vol 23 (10) ◽  
pp. 101587
Author(s):  
Wentao Yu ◽  
Han Zhang ◽  
Ping-An Yin ◽  
Fan Zhou ◽  
Zhiming Wang ◽  
...  
Keyword(s):  
Excited State ◽  
Building Block ◽  
Aggregation Induced Emission ◽  
Block Based
Sign in / Sign up

Export Citation Format

Share Document