Photochemical Cycloaddition of Singlet and Triplet Diphenylvinylene Carbonate with Vinyl Ethers

Frederick D. Lewis; Richard H. Hirsch; Paula M. Roach; Douglas E. Johnson

doi:10.1021/ja00442a021

Photochemical Cycloaddition of Singlet and Triplet Diphenylvinylene Carbonate with Vinyl Ethers

Frederick D. Lewis, Richard H. Hirsch, Paula M. Roach, Douglas E. Johnson

Chemistry

Research output: Contribution to journal › Article › peer-review

16 Scopus citations

Abstract

The singlet and triplet excited states of diphenylvinylene carbonate (V) react with vinyl ethers to produce 2 + 2 cycloadducts. Weak exciplex emission is observed when the fluorescence of V is quenched by high concentrations of 2-methyl-1-methoxypropene. Rate constants for fluorescence quenching and limiting quantum yields for singlet cycloaddition increase with decreasing vinyl ether ionization potential, in accord with an exciplex mechanism for cycloaddition. The solvent dependence of the cycloaddition quantum yields is indicative of a moderately polar exciplex. Singlet addition to the isomeric 1-methoxypropenes is stereospecific, whereas triplet addition proceeds with substantial loss of stereochemistry. Comparison of solvent effects and adduct stereochemistry for the singlet and triplet addition reactions suggests that a triplet exciplex is the precursor of a triplet biradical intermediate.

Original language	English (US)
Pages (from-to)	8438-8446
Number of pages	9
Journal	Journal of the American Chemical Society
Volume	98
Issue number	26
DOIs	https://doi.org/10.1021/ja00442a021
State	Published - Dec 1 1976

ASJC Scopus subject areas

Catalysis
Chemistry(all)
Biochemistry
Colloid and Surface Chemistry

Access to Document

10.1021/ja00442a021

Cite this

@article{6baf0c0ada0a416b92d7b41de343191f,

title = "Photochemical Cycloaddition of Singlet and Triplet Diphenylvinylene Carbonate with Vinyl Ethers",

abstract = "The singlet and triplet excited states of diphenylvinylene carbonate (V) react with vinyl ethers to produce 2 + 2 cycloadducts. Weak exciplex emission is observed when the fluorescence of V is quenched by high concentrations of 2-methyl-1-methoxypropene. Rate constants for fluorescence quenching and limiting quantum yields for singlet cycloaddition increase with decreasing vinyl ether ionization potential, in accord with an exciplex mechanism for cycloaddition. The solvent dependence of the cycloaddition quantum yields is indicative of a moderately polar exciplex. Singlet addition to the isomeric 1-methoxypropenes is stereospecific, whereas triplet addition proceeds with substantial loss of stereochemistry. Comparison of solvent effects and adduct stereochemistry for the singlet and triplet addition reactions suggests that a triplet exciplex is the precursor of a triplet biradical intermediate.",

author = "Lewis, {Frederick D.} and Hirsch, {Richard H.} and Roach, {Paula M.} and Johnson, {Douglas E.}",

year = "1976",

month = dec,

day = "1",

doi = "10.1021/ja00442a021",

language = "English (US)",

volume = "98",

pages = "8438--8446",

journal = "Journal of the American Chemical Society",

issn = "0002-7863",

publisher = "American Chemical Society",

number = "26",

}

TY - JOUR

T1 - Photochemical Cycloaddition of Singlet and Triplet Diphenylvinylene Carbonate with Vinyl Ethers

AU - Lewis, Frederick D.

AU - Hirsch, Richard H.

AU - Roach, Paula M.

AU - Johnson, Douglas E.

PY - 1976/12/1

Y1 - 1976/12/1

N2 - The singlet and triplet excited states of diphenylvinylene carbonate (V) react with vinyl ethers to produce 2 + 2 cycloadducts. Weak exciplex emission is observed when the fluorescence of V is quenched by high concentrations of 2-methyl-1-methoxypropene. Rate constants for fluorescence quenching and limiting quantum yields for singlet cycloaddition increase with decreasing vinyl ether ionization potential, in accord with an exciplex mechanism for cycloaddition. The solvent dependence of the cycloaddition quantum yields is indicative of a moderately polar exciplex. Singlet addition to the isomeric 1-methoxypropenes is stereospecific, whereas triplet addition proceeds with substantial loss of stereochemistry. Comparison of solvent effects and adduct stereochemistry for the singlet and triplet addition reactions suggests that a triplet exciplex is the precursor of a triplet biradical intermediate.

AB - The singlet and triplet excited states of diphenylvinylene carbonate (V) react with vinyl ethers to produce 2 + 2 cycloadducts. Weak exciplex emission is observed when the fluorescence of V is quenched by high concentrations of 2-methyl-1-methoxypropene. Rate constants for fluorescence quenching and limiting quantum yields for singlet cycloaddition increase with decreasing vinyl ether ionization potential, in accord with an exciplex mechanism for cycloaddition. The solvent dependence of the cycloaddition quantum yields is indicative of a moderately polar exciplex. Singlet addition to the isomeric 1-methoxypropenes is stereospecific, whereas triplet addition proceeds with substantial loss of stereochemistry. Comparison of solvent effects and adduct stereochemistry for the singlet and triplet addition reactions suggests that a triplet exciplex is the precursor of a triplet biradical intermediate.

UR - http://www.scopus.com/inward/record.url?scp=33847797922&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33847797922&partnerID=8YFLogxK

U2 - 10.1021/ja00442a021

DO - 10.1021/ja00442a021

M3 - Article

AN - SCOPUS:33847797922

SN - 0002-7863

VL - 98

SP - 8438

EP - 8446

JO - Journal of the American Chemical Society

JF - Journal of the American Chemical Society

IS - 26

ER -

Photochemical Cycloaddition of Singlet and Triplet Diphenylvinylene Carbonate with Vinyl Ethers

Abstract

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this