Abstract:
:Photolysis of ester 1 in argon-saturated methanol and acetonitrile does not produce any product, whereas irradiation of 1 in oxygen-saturated methanol yields peroxide 2. Laser flash photolysis studies demonstrate that 1 undergoes intramolecular H atom abstraction to form biradical 3 (λmax ~340 nm), which intersystem crosses to form photoenols Z-4 and E-4 (λmax ~380 nm). Photoenols 4 decay by regenerating ester 1. With the aid of density functional theory calculations, it was concluded the photoenol E-4 does not undergo spontaneous lactonization or electrocyclic ring closure because the transition state barriers for these reactions are too large to compete with reketonization of E-4 to form 1.
journal_name
Photochem Photobioljournal_title
Photochemistry and photobiologyauthors
Das A,Lao EA,Gudmundsdottir ADdoi
10.1111/php.12590subject
Has Abstractpub_date
2016-05-01 00:00:00pages
388-98issue
3eissn
0031-8655issn
1751-1097journal_volume
92pub_type
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