Lamp versus laser photolysis of a bichromophoric dichloroalkane: Chemical evidence for the two-photon generation of the 1,5-diphenylpentanediyl biradical

Overview

Title: 

Lamp versus laser photolysis of a bichromophoric dichloroalkane: Chemical evidence for the two-photon generation of the 1,5-diphenylpentanediyl biradical

Abstract: 

Low intensity (lamp) photolysis of 1,5-dichloro-1,5-diphenylpentane (1) leads to the formation of the 1-chloro-1,5-diphenylpentyl radical (7) through C-CI bond cleavage. Radical 7 leads to the final products through typical free radical reactions. No cyclopentanes are formed under low intensity conditions. In contrast, high intensity laser irradiation leads to C-Cl photocleavage of radical 7 to yield the 1,5-diphenylpentanediyl biradical (11), which results in the formation of isomeric cis- and trans-1,2-diphenylcyclopentanes; the behavior of these biradicals agrees well with that observed when their precursor is 2,6-diphenylcyclohexanone. Two-color two-laser experiments suggest that both singlet and triplet biradicals are formed, even if only the latter are detectable with nanosecond techniques.

Authors: 

Julia Pérez-Prieto, Miguel Angel Miranda, Hermenegildo García, Klára Kónya, J. C. Scaiano

DOI: 

Journal: 

Journal Of Organic Chemistry

Year: 

1996

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