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Title: Competing pathways for photoremovable protecting groups: the effects of solvent, oxygen and encapsulation
Extending the applications of Photoremovable Protecting Groups (PPGs) to “cage” phenols has generally met with unusually complex PPG byproducts. In this study, we demonstrate that the p –hydroxyphenacyl (pHP) cage for both simple and complex phenolics, including tyrosine, dispenses free phenols. With the simpler unsubstituted phenols, the reaction is governed by their Brønsted Leaving Group ability. On the other hand, the byproducts of the cage vary with these phenols. For the more acidic phenols the cage byproduct follows the Favorskii rearrangement to form p -hydroxyphenylacetic acid whereas for the weaker phenols other reactions such as reduction and hydrolysis begin to emerge. When the photolysis is conducted in octa acid (OA) containers, non-Favorskii, unrearranged fragments of the cage and other byproducts arise.  more » « less
Award ID(s):
1807729
PAR ID:
10283666
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Photochemical & Photobiological Sciences
Volume:
19
Issue:
10
ISSN:
1474-905X
Page Range / eLocation ID:
1364 to 1372
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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