A Convenient Method for Protection and Deprotection of Alcohols and Phenols as Alkylsilyl Ethers Catalyzed by Iodine Under Microwave Irradiation
作者:Ira Saxena、Nabajyoti Deka、Jadab C. Sarma、Sadao Tsuboi
DOI:10.1081/scc-120026335
日期:2003.12.1
Abstract Irradiation of alcohols or phenols with tert-butyldimethylsilyl chloride (TBDMSCl) or trimethylsilyl chloride (TMSCl) in presence of catalytic amount (20 mol%) of iodine in a microwave oven for 2 min gives the corresponding silyl ethers in excellent yield. Iodine in methanol deprotects the silyl ether into its parent alcohol or phenol under similar reaction conditions.
primary and secondary alcohols and phenols can be converted efficiently to their corresponding TBDMS ethers using TBDMCS/imidazole undersolvent-freeconditions. Elimination of DMF, accompanied with an easy non-aqueous work-up and a high rate enhancement of the reaction are worthy to be mentioned for the presented method. The reactions show absolute chemoselectivity for the protection of primary in the
Amine-free silylation of various alcohols catalyzed by 4-methylpyridine N-oxide in the presence of MS4A at room temperature was developed. This simple method gave various silyl ethers in a high yield. (C) 2015 Elsevier Ltd. All rights reserved.