A convenient and high yielding method for the cleavage and scavenging of p-methoxybenzyl protecting group of several alcohols using tert-butyl bromide in refluxing acetonitrile is described. Under these mild conditions other protecting groups such as acid sensitive allyl, benzyl, and Me3CPh2Si ethers, or isopropylidene acetals were unchanged. Interestingly, a selective alkoxy-PMB cleavage was observed
A Novel, Chemoselective and Efficient Microwave-Assisted Deprotection of Silyl Ethers with Selectfluor
作者:Syed Tasadaque A. Shah、Surendra Singh、Patrick J. Guiry
DOI:10.1021/jo802494t
日期:2009.3.6
efficient method for the cleavage of silyl ethers (aliphatic and aromatic) catalyzed by Selectfluor is reported. A wide range of TBS-, TIPS-, and TBDPS-protected alkyl silyl ethers can be chemoselectively cleaved in high yield in the presence of aryl silyl ethers. The chemoselective deprotection of phenolic TBS ethers, and not the TIPS- or TBDPS-protected phenolic ethers, and the deprotection of silyl esters
Selective deprotection of alkyl vs. aryl silyl ethers
作者:Bruce H Lipshutz、John Keith
DOI:10.1016/s0040-4039(98)00381-5
日期:1998.4
Alkyl silyl ethers, in particular t-butyldimethylsilyl derivatives, can be selectively cleaved in high yields over aryl silyl ethers using small percentages of I2 in MeOH at ambient temperatures.
A simple and efficient method has been developed for the hydrolysis of methoxymethyl (MOM) ethers and esters to the corresponding alcohols and acids employing a catalytic amount of bismuth triflate in an aqueous medium. The conversions occur at ambient temperature and the yields of the deprotected alcohols are very good. The reaction was highly selective in the presence of other protecting groups such
Efficient chemoselective deprotection of silyl ethers using catalytic 1-chloroethyl chloroformate in methanol
作者:Chang-Eun Yeom、Young Jong Kim、So Young Lee、Yong Je Shin、B. Moon Kim
DOI:10.1016/j.tet.2005.10.043
日期:2005.12
Fast and chemoselective desilylation of silyl-protected alcohols was achieved using a catalytic amount of 1-chloroethyl chloroformate in methanol. With a minimal amount of 1-chloroethyl chloroformate as the source for anhydrous HCl, extremely efficient cleavage of silyl ethers of primary and secondary alcohols was accomplished, and chemoselective deprotection of one silyl ether in the presence of another silyl or other acid-labile group was possible through controlling the amount of the chloroformate and reaction time. (c) 2005 Elsevier Ltd. All rights reserved.