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Insertion of phenylchlorocarbenes in the CH bonds of alkanes: measurement of the rate constants by laser flash photolysis

✍ Scribed by R. Bonneau; M.T.H. Liu

Publisher
Elsevier Science
Year
1992
Tongue
English
Weight
774 KB
Volume
68
Category
Article
ISSN
1010-6030

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✦ Synopsis

Phenylchlorocarbenes

, produced by photolysis of the parent diazirines, have a very limited lifetime in alkane solvents. The rate of dibappearance of p-methyl-and p-chlorophenylchlorocarbenes has been measured in iso-octane, cyclohexane and n-hexane as well as in benzene for comparison. The rate constants of several procesies (dimerization, addition to the diazirine, reaction with the solvent, etc. ) contributing to the disappearance of the phenylchlorocarbenes have been determined. The rate of reaction with the solvent, which is much lower in benzene than in alkanes and depends strongly on the nature of the alkane, is assumed to be an insertion of the carbene in the C-H bonds of the solvent. Consequences of this reaction on the chemistry of carbenes produced by continuous irradiation (or therrnolysis) of diazirines in alkanes are briefly discussed.

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