Uncovering New Excited State Photochemical Reactivity by Altering the Course of the De Mayo Reaction

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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ChemInform Abstract: THE PHOTOCHEMICAL REACTIVITY OF SOME BENZOYLTHIOPHENES PART 3, THE EFFECT OF AN ADJACENT METHYL GROUP ON THE EXCITED STATE REACTIVITY OF 2-BENZOYLTHIOPHENE

Chemischer Informationsdienst ◽

10.1002/chin.197517141 ◽

1975 ◽

Vol 6 (17) ◽

pp. no-no

Author(s):

D. R. ARNOLD ◽

B. M. JUN. CLARKE

Keyword(s):

Excited State ◽

Photochemical Reactivity ◽

Methyl Group

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Five decades of mechanistic and exploratory organic photochemistry

Pure and Applied Chemistry ◽

10.1351/pac200678122193 ◽

2006 ◽

Vol 78 (12) ◽

pp. 2193-2203 ◽

Cited By ~ 20

Author(s):

Howard E. Zimmerman

Keyword(s):

Excited State ◽

Electronic Structures ◽

Personal Perspective ◽

Photochemical Reactivity ◽

The Third ◽

Organic Photochemistry

This exposition summarizes a personal perspective on past and current developments in organic photochemistry. It comprises three portions. The first section describes the beginnings of our photochemical studies and how it was possible to relate photochemical reactivity to excited-state electronic structures. The second selectively relates some of the reactions and concepts developed in the intermediate years. Finally, the third portion describes our recent research.

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Singlet and Triplet Excited-State Interactions and Photochemical Reactivity of Phenyleneethynylene Oligomers

The Journal of Physical Chemistry A ◽

10.1021/jp0603637 ◽

2006 ◽

Vol 110 (17) ◽

pp. 5642-5649 ◽

Cited By ~ 38

Author(s):

P. K. Sudeep ◽

P. V. James ◽

K. George Thomas ◽

Prashant V. Kamat

Keyword(s):

Excited State ◽

Triplet Excited State ◽

Photochemical Reactivity

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Renilla Bioluminescence: A Morphologic Approach to the Location of Photocytes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100051050 ◽

1974 ◽

Vol 32 ◽

pp. 208-209

Author(s):

Ben O. Spurlock ◽

Milton J. Cormier

Keyword(s):

Excited State ◽

Ground State ◽

Molecular Basis ◽

Light Emission ◽

Chemical Basis ◽

Electronic Excited State ◽

Colonial Form ◽

The Common ◽

Eighteenth And Nineteenth Centuries ◽

Catalyzed Oxidation

The phenomenon of bioluminescence has fascinated layman and scientist alike for many centuries. During the eighteenth and nineteenth centuries a number of observations were reported on the physiology of bioluminescence in Renilla, the common sea pansy. More recently biochemists have directed their attention to the molecular basis of luminosity in this colonial form. These studies have centered primarily on defining the chemical basis for bioluminescence and its control. It is now established that bioluminescence in Renilla arises due to the luciferase-catalyzed oxidation of luciferin. This results in the creation of a product (oxyluciferin) in an electronic excited state. The transition of oxyluciferin from its excited state to the ground state leads to light emission.

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Integration of Core-Edge Spectroscopy Methods for the Study of Polymers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010016323x ◽

1996 ◽

Vol 54 ◽

pp. 154-155

Author(s):

E. G. Rightor

Keyword(s):

Excited State ◽

Polymer Blends ◽

Gas Phase ◽

Spatial Resolution ◽

High Spatial Resolution ◽

Electronic States ◽

Core Electron ◽

Bulk Solids ◽

Development Application

Core edge spectroscopy methods are versatile tools for investigating a wide variety of materials. They can be used to probe the electronic states of materials in bulk solids, on surfaces, or in the gas phase. This family of methods involves promoting an inner shell (core) electron to an excited state and recording either the primary excitation or secondary decay of the excited state. The techniques are complimentary and have different strengths and limitations for studying challenging aspects of materials. The need to identify components in polymers or polymer blends at high spatial resolution has driven development, application, and integration of results from several of these methods.

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Examining the degradation of environmentally-daunting per- and poly-fluoroalkyl substances from a fundamental chemical perspective

Physical Chemistry Chemical Physics ◽

10.1039/d0cp02445g ◽

2020 ◽

Vol 22 (31) ◽

pp. 17659-17667 ◽

Cited By ~ 2

Author(s):

Antonio H. da S. Filho ◽

Gabriel L. C. de Souza

Keyword(s):

Excited State

In this work, ground and excited-state properties were used as descriptors for probing mechanisms as well as to assess potential alternatives for tackling the elimination of per- and poly-fluoroalkyl substances (PFAS).

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