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Title: Role of curvature in acridone for 1O2 oxidation of a natural product homoallylic alcohol: A novel iso ‐hydroperoxide intermediate
Abstract

A density functional theoretical (DFT) study is presented, implicating a1O2oxidation process to reach a dihydrobenzofuran from the reaction of the natural homoallylic alcohol, glycocitrine. Our results predict an interconversion between glycocitrine and aniso‐hydroperoxide intermediate [R(H)O+O] that provides a key path in the chemistry which then follows. Formations of allylic hydroperoxides are unlikely from a1O2‘ene’ reaction. Instead, the dihydrobenzofuran arises by1O2oxidation facilitated by a 16° curvature of the glycocitrine ring imposed by a pyramidalN‐methyl group. This curvature facilitates the formation of theiso‐hydroperoxide, which is analogous to theisospecies CH2I+Iand CHI2+Iformed by UV photolysis of CH2I2and CHI3. Theiso‐hydroperoxide is also structurally reminiscent of carbonyl oxides (R2C=O+O) formed in the reaction of carbenes and oxygen. Our DFT results point to intermolecular process, in which theiso‐hydroperoxide's fate relates to O‐transfer and H2O dehydration reactions for new insight into the biosynthesis of dihydrobenzofuran natural products.

 
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Award ID(s):
2154133
NSF-PAR ID:
10444559
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Photochemistry and Photobiology
ISSN:
0031-8655
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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