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Photosensitized reactions of conjugated dienes


Liu, Robert Shing-Hei (1965) Photosensitized reactions of conjugated dienes. Dissertation (Ph.D.), California Institute of Technology.


Conjugated dienes are shown to undergo photosensitized dimerization reaction, photosensitized cross addition reaction, and photosensitized inter- or intramolecular addition to olefins. Structures of isoprene, piperylenes, 2, 3dimethylbutadiene dimers, butadiene-1, 3-cyclohexadiene, 1, 3-cyclohexadiene-cyclopentene cross adducts, and myrcene photoisomers have been assigned (some in parts). The mechanism of the dimerization reaction, which is closely related to the other reactions, has been studied in detail with isoprene as the representative system. It was found that in order to explain the results consistently, several postulates are necessarily invoked. They include the non-interconvertible stereoisomeric triplets of conjugated diene, the unusual stable nuclei configuration of diene triplets, new assignments of the O-O components of singlet-triplet transition of dienes, and "nonvertical" energy transfer from sensitizer to diene molecules. Evidence is presented in support of the mechanism in which only one diene triplet is involved in such a bimolecular reaction.

Item Type:Thesis (Dissertation (Ph.D.))
Degree Grantor:California Institute of Technology
Division:Chemistry and Chemical Engineering
Major Option:Chemistry
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Hammond, George Simms
Thesis Committee:
  • Unknown, Unknown
Defense Date:22 September 1964
Record Number:CaltechETD:etd-10012002-095952
Persistent URL:
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:3844
Deposited By: Imported from ETD-db
Deposited On:01 Oct 2002
Last Modified:26 Dec 2012 03:03

Thesis Files

PDF (Liu_rs_1965.pdf) - Final Version
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