ChemInform Abstract: A Synthetically Useful Source of Propargyl Radicals.

S-Propargyl xanthates undergo upon heating a [3,3] sigmatropic rearrangement followed by a reversible ring closure into a novel betaine. This betaine can be implicated in carbon–carbon bond forming processes, in the synthesis of esters, in the inversion of secondary alcohols, in the formation of alkenes, for the generation of rigid, cisoid dienes that are highly reactive in both inter- and intra-molecular Diels–Alder cycloadditions, and in various other synthetically useful transformations.1 Introduction2 An Unexpected Transformation3 Evidence for the Betaine Intermediate4 A Method for the Synthesis of Esters and for the Inversion of Secondary Alcohols5 A General Alkylation Process6 The Case of Carbon Acids7 A Synthesis of Alkenes8 Further Trapping Experiments. Concerted or Not Concerted?9 Rigid Cisoid Dienes10 Propargyl Radicals11 Concluding Remarks

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Substituent effect on electron affinity, gas-phase basicity, and structure of monosubstituted propargyl radicals and their anions: a theoretical study

Journal of Physical Organic Chemistry ◽

10.1002/poc.1579 ◽

2009 ◽

pp. n/a-n/a

Author(s):

Gab-Yong Lee

Keyword(s):

Gas Phase ◽

Electron Affinity ◽

Substituent Effect ◽

Theoretical Study ◽

Propargyl Radicals

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Photofragment translational spectroscopy of propargyl radicals at 248nm

The Journal of Chemical Physics ◽

10.1063/1.2840350 ◽

2008 ◽

Vol 128 (11) ◽

pp. 114303 ◽

Cited By ~ 16

Author(s):

Scott J. Goncher ◽

David T. Moore ◽

Niels E. Sveum ◽

Daniel M. Neumark

Keyword(s):

Propargyl Radicals

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FREE RADICALS BY MASS SPECTROMETRY: VII. THE IONIZATION POTENTIALS OF ETHYL, ISOPROPYL, AND PROPARGYL RADICALS AND THE APPEARANCE POTENTIALS OF THE RADICAL IONS IN SOME DERIVATIVES

Canadian Journal of Chemistry ◽

10.1139/v55-104 ◽

1955 ◽

Vol 33 (5) ◽

pp. 861-869 ◽

Cited By ~ 57

Author(s):

J. B. Farmer ◽

F. P. Lossing

Keyword(s):

Mass Spectrometry ◽

Thermal Decomposition ◽

Free Radicals ◽

Kinetic Energy ◽

Electron Impact ◽

Ionization Potentials ◽

Bond Dissociation Energies ◽

Radical Ions ◽

Dissociation Energies ◽

Propargyl Radicals

The ionization potentials of ethyl, isopropyl, and propargyl radicals have been measured by electron impact on radicals produced by thermal decomposition of appropriate compounds. The values are:ethyl 8.78±0.05 ev., isopropyl 7.90±0.05 ev., and propargyl 8.25±0.08 ev. From the appearance potentials of these ions in various compounds, the following values of bond dissociation energies were obtained:[Formula: see text][Formula: see text] assuming no kinetic energy of the products.

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Photolyse du butyne-1 dans la région de 147 à 174 nm

Canadian Journal of Chemistry ◽

10.1139/v80-334 ◽

1980 ◽

Vol 58 (19) ◽

pp. 2100-2107 ◽

Cited By ~ 4

Author(s):

Hélène Deslauriers ◽

Jovette Deschênes ◽

Guy J. Collin

Keyword(s):

Quantum Yield ◽

Radical Scavenging ◽

Hydrogen Iodide ◽

Radical Scavengers ◽

Methyl Radical ◽

Radical Intermediate ◽

Scavenging Effect ◽

Radical Scavenging Effect ◽

Propargyl Radicals

We have studied the 147, 163, and 174 nm photolysis of 1-butyne. Several products from C1 to C5 were observed under various conditions such as in the presence of additives, or at different pressures between 0.5 and 100 Torr (65 to 13 300 N m−2). The methyl radical is the most important radical intermediate. Acetylene, ethylene, and vinylacetylene are produced in the presence of radical scavengers and are probably the result of the fragmentation of the photoexcited molecule. Propargyl radicals are thought to be produced but appear not to be scavenged by hydrogen iodide. Polymerization was observed even in the presence of radical scavengers. Secondary processes are numerous and make the interpretation of our results difficult; for example, the ethylene quantum yield increased upon addition of 10% oxygen, the simple radical scavenging effect of this additive does not explain such an effect.

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