Positional chemoselectivity in the Zn(II)-mediated removal of phenol protecting groups
摘要:
A protocol was developed for the chemoselective ortho-deprotection of polyphenolic substrates using readily available (ZnX2)-X-II salts. This procedure provides exceptional positional selectivity for the deprotection of phenols that reside adjacent to directing carbonyl functionality in the presence of similar protecting groups at the meta and para positions. Good to excellent yields of the desired free phenols were obtained (<= 96%), and a wide assortment of protecting groups was readily removed under the reaction conditions. (C) 2012 Elsevier Ltd. All rights reserved.
Modulating Twisted Amide Geometry and Reactivity Through Remote Substituent Effects
作者:Mizhi Xu、McKinley K. Paul、Krista K. Bullard、Christopher DuPre、Will R. Gutekunst
DOI:10.1021/jacs.1c05854
日期:2021.9.15
The unusual reactivity of twisted amides has long been associated with the degree of amide distortion, though classical bridged bicyclic amides offer limited methods to further modify these parameters. Here, we report that the geometry and reactivity of a single twisted amide scaffold can be significantly modulated through remote substituenteffects. Guided by calculated ground state geometries, a
Positional chemoselectivity in the Zn(II)-mediated removal of phenol protecting groups
作者:Lauren M. Fleury、Joseph B. Gianino、Brandon L. Ashfeld
DOI:10.1016/j.tetlet.2012.07.103
日期:2012.10
A protocol was developed for the chemoselective ortho-deprotection of polyphenolic substrates using readily available (ZnX2)-X-II salts. This procedure provides exceptional positional selectivity for the deprotection of phenols that reside adjacent to directing carbonyl functionality in the presence of similar protecting groups at the meta and para positions. Good to excellent yields of the desired free phenols were obtained (<= 96%), and a wide assortment of protecting groups was readily removed under the reaction conditions. (C) 2012 Elsevier Ltd. All rights reserved.