Chemoselective Oxidation of <i>p</i>-Methoxybenzyl Ethers by an Electronically Tuned Nitroxyl Radical Catalyst
作者:Shohei Hamada、Koichi Sugimoto、Elghareeb E. Elboray、Takeo Kawabata、Takumi Furuta
DOI:10.1021/acs.orglett.0c01839
日期:2020.7.17
The oxidation of p-methoxy benzyl (PMB) ethers was achieved using nitroxylradicalcatalyst 1, which contains electron-withdrawing ester groups adjacent to the nitroxyl group. The oxidative deprotection of the PMB moieties on the hydroxy groups was observed upon treatment of 1 with 1 equiv of the co-oxidant phenyl iodonium bis(trifluoroacetate) (PIFA). The corresponding carbonyl compounds were obtained
Oxidative Cleavage of <i>p</i>-Methoxybenzyl Ethers with Methyl(trifluoromethyl)dioxirane
作者:Leo A. Paquette、Matthew M. Kreilein、Matthew W. Bedore、Dirk Friedrich
DOI:10.1021/ol051856h
日期:2005.10.1
[reaction: see text] The ability of methyl(trifluoromethyl)dioxirane to cleave p-methoxylbenzyl ethers oxidatively in the presence of various additional functional groups has been investigated. These reactions, performed in aqueous acetonitrile, transform a reasonably robust aryl substituent into a dienyl aldehydo ester. The originally generated E,Z-isomer undergoes slow conversion to the more stable
Aerobic oxidative deprotection of benzyl-type ethers under atmospheric pressure catalyzed by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ)/tert-butyl nitrite
作者:Zhenlu Shen、Lili Sheng、Xiaochu Zhang、Weimin Mo、Baoxiang Hu、Nan Sun、Xinquan Hu
DOI:10.1016/j.tetlet.2013.01.045
日期:2013.3
efficient protocol for the oxidativedeprotection of benzyl-type ethers has been developed. The reaction was performed with catalytic amounts of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) and tert-butyl nitrite (TBN) under atmospheric pressure of O2. Under the optimal reaction conditions, a variety of p-methoxybenzyl (PMB), p-phenylbenzyl (PPB), and benzyl (Bn) ethers can be deprotected to their
Facile oxidation of benzyl ethers by the 2-nitrobenzenesulfonylperoxyl intermediate generated from 2-nitrobenzenesulfonyl chloride and superoxide
作者:Yong Hae Kim、Yong Il Kim、Joong Young Kim
DOI:10.1039/a800106e
日期:——
Various benzyl ethers react with a 2-nitrobenzenesulfonylperoxyl radical intermediate generated from 2-nitrobenzenesulfonyl chloride and potassium superoxide at –25 °C in acetonitrile to give the corresponding esters in high yields.
ZEOLITE-MEDIATED CONVERSION OF ALCOHOLS TO<i>p</i>-METHOXYBENZYL ETHERS
作者:G. V. M. Sharma、Sreenivas Punna、A. Ratnamala、V. Durga Kumari、M. Subrahmanyam
DOI:10.1080/00304940409355975
日期:2004.12
The protection of functional groups1 is very important for the successful synthesis of complex molecules. The p-methoxybenzyl (PMB) and 3,4dimethoxybenzyl @MB) groups have proven their usefulness for the protection of hydroxy groups because of the ease with which they can be removed under neutral and mild conditions [2,3-dichloro-5,6 dicyano-benzO-l,4quinone (DDQ) in aqueous dichloromethane2 or DDQ-M~(OAC)