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Title: Sensitized Photooxidation of Ortho ‐Prenyl Phenol: Biomimetic Dihydrobenzofuran Synthesis and Total 1O2 Quenching †
Abstract

The sensitized photooxidation ofortho‐prenyl phenol is described with evidence that solvent aproticity favors the formation of a dihydrobenzofuran [2‐(prop‐1‐en‐2‐yl)‐2,3‐dihydrobenzofuran], a moiety commonly found in natural products. Benzene solvent increased the total quenching rate constant (kT) of singlet oxygen with prenyl phenol by ~10‐fold compared to methanol. A mechanism is proposed with preferential addition of singlet oxygen to prenyl site due to hydrogen bonding with the phenol OH group, which causes a divergence away from the singlet oxygen ‘ene’ reaction toward the dihydrobenzofuran as the major product. The reaction is a mixed photooxidized system since an epoxide arises by a type I sensitized photooxidation.

 
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Award ID(s):
2154133 1856765
PAR ID:
10371150
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Photochemistry and Photobiology
Volume:
99
Issue:
2
ISSN:
0031-8655
Page Range / eLocation ID:
p. 637-641
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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