Intersystem crossing in styrene and styrene derivatives

We describe a new family of catalysts that undergo direct ground state singlet to excited state triplet excitation with IR light, leading to photoredox catalysis without the energy waste associated with intersystem crossing. The finding allows a mole scale reaction in batch using infrared irradiation.

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Visible Light-Induced Sulfonylation/Arylation of Styrenes in a Double Radical Three-Component Photoredox Reaction

10.26434/chemrxiv.7722020.v1 ◽

2019 ◽

Author(s):

Benjamin Lipp ◽

Lisa Marie Kammer ◽

Murat Kucukdisli ◽

Adriana Luque ◽

Jonas Kühlborn ◽

...

Keyword(s):

Visible Light ◽

Radical Formation ◽

Three Component Reaction ◽

Broad Variety ◽

Styrene Derivatives ◽

Mechanistic Investigations

Simultaneous sulfonylation/arylation of styrene derivatives is achieved in a photoredox-catalyzed three-component reaction using visible light. A broad variety of difunctionalized products is accessible in mostly excellent yields and high diastereoselectivity. The developed reaction is scalable and suitable for the modification of styrene-functionalized biomolecules. Mechanistic investigations suggest the transformation to be operating through a designed sequence of radical formation and radical combination.<br>

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[OsH4(PPh3)3]: New Catalyst for the Selective Cyclopropanation of Activated Olefins

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19961798 ◽

1996 ◽

Vol 61 (12) ◽

pp. 1798-1804 ◽

Cited By ~ 2

Author(s):

Albert Demonceau ◽

François Simal ◽

Corine A. Lemoine ◽

Alfred F. Noels ◽

Igor T. Chizhevsky ◽

...

Keyword(s):

Title Compound ◽

Efficient Catalyst ◽

Ethyl Diazoacetate ◽

Styrene Derivatives ◽

Activated Olefins ◽

Cyclic Alkenes

The title compound was found to be an efficient catalyst for the selective cyclopropanation of activated olefins by ethyl diazoacetate. The cyclopropane yields range from moderate to good (75 to 95%) for activated olefins such as styrene and styrene derivatives, but are rather low (20 to 30%) for non-activated olefins such as terminal and cyclic alkenes. In the intermolecular competition, styrene was 45 times more reactive than cyclooctene. In all cases, trans (exo) cyclopropane predominated over the cis (endo) isomer.

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Intersystem crossing processes in the 2CzPN emitter: a DFT/MRCI study including vibrational spin–orbit interactions

Physical Chemistry Chemical Physics ◽

10.1039/d0cp06011a ◽

2021 ◽

Vol 23 (5) ◽

pp. 3668-3678

Author(s):

Angela Rodriguez-Serrano ◽

Fabian Dinkelbach ◽

Christel M. Marian

Keyword(s):

Quantum Chemical Calculations ◽

Quantum Chemical ◽

Intersystem Crossing ◽

Spin Orbit ◽

Spin Orbit Interactions

Multireference quantum chemical calculations were performed in order to investigate the (reverse) intersystem crossing ((R)ISC) mechanisms of 4,5-di(9H-carbazol-9-yl)-phthalonitrile (2CzPN).

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Synthesis and properties of EPDM-based oil-absorptive gels with different types of EPDM and styrene derivatives

RSC Advances ◽

10.1039/d0ra08409c ◽

2021 ◽

Vol 11 (3) ◽

pp. 1605-1613

Author(s):

Minghua Zhang ◽

Minmin Fan ◽

Shuhua Peng ◽

Jianping He ◽

Mingyu Deng ◽

...

Keyword(s):

Different Types ◽

Styrene Derivatives

The effects of EPDM types and styrene derivatives on the properties of EPDM-based oil-absorptive gels were studied.

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Electron transfer sensitized photolysis of 'onium salts

Canadian Journal of Chemistry ◽

10.1139/v88-055 ◽

1988 ◽

Vol 66 (2) ◽

pp. 319-324 ◽

Cited By ~ 55

Author(s):

R. J. DeVoe ◽

M. R. V. Sahyun ◽

Einhard Schmidt ◽

N. Serpone ◽

D. K. Sharma

Keyword(s):

Electron Transfer ◽

Flash Photolysis ◽

Laser Flash Photolysis ◽

Laser Flash ◽

Quantitative Model ◽

Intersystem Crossing ◽

Single Electron Transfer ◽

Onium Salts ◽

Encounter Complex ◽

Back Electron Transfer

We have studied the anthracene-sensitized photolyses of both diphenyliodonium and triphenylsulphonium salts in solution using both steady-state and laser flash photolysis techniques. Photoproducts, namely, phenylated anthracenes along with iodobenzene or diphenylsulphide, respectively, are obtained from both salts with quantum efficiencies of ca. 0.1 at 375 nm. We infer the intermediacy of diphenyliodo and triphenylsulphur radicals formed by single electron transfer from the singlet-excited anthracene. We have developed a quantitative model of this chemistry, and identify the principal sources of inefficiency as back electron transfer, which occurs at nearly the theoretically limiting rate, intersystem crossing from the initially formed sensitizer–'onium salt encounter complex, and in-cage radical recombination.

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