6221-90-5Relevant academic research and scientific papers
Trimethylsilyl Esters as Novel Dual-Purpose Protecting Reagents
Chen, Jyun-Siao,Huang, Po-Hsun,Hsieh, Ya-Chi,Liu, Jen-Wei,Hsu, Hsiao-Lin,Zhang, Kai-Min,Wu, Ren-Tsung,Chang, Ting-Shuo,Liu, Yu-Hao,Wu, Hsin-Ru,Luo, Shun-Yuan
supporting information, p. 754 - 762 (2021/12/02)
Trimethylsilyl esters, AcOTMS, BzOTMS, TCAOTMS, etc., are inexpensive and chemically stable reagents that pose a negligible environmental hazard. Such compounds prove to serve as efficient dualpurpose reagents to respectively achieve acylation and trimethylsilylation of alcohols under acidic or basic conditions. Herein, a detailed study on protection of various substrates and new methodological investigations is described.
Highly atom economical uncatalysed and I2-catalysed silylation of phenols, alcohols and carbohydrates, using HMDS under solvent-free reaction conditions (SFRC)
Jereb, Marjan
experimental part, p. 3861 - 3867 (2012/06/30)
An uncatalysed silylation of phenols, regardless on the aggregate state and nature of the substituents with 0.55 equiv of HMDS under solvent-free reaction conditions (SFRC) at room temperature is reported. Sterically hindered phenols, carbohydrates and most of the alcohols additionally required a catalytic amount (up to 2 mol %) of iodine. The reaction protocol is very simple; obtaining a pure product, particularly of uncatalysed reactions, was frequently a completely solvent-free process.
Novel and highly effective method for the trimethylsilylation of alcohols and phenols with hexamethyldisilazane (HMDS), catalyzed by I2 generated in situ using Fe(NO3)3 · 9 H 2O/NaI under heterogeneous and neutral conditions
Khazaei, Ardeshir,Rahmati, Sadegh,Rostami, Amin
experimental part, p. 1434 - 1438 (2009/10/16)
Structurally diverse alcohols and phenols were trimethylsilylated in a clean and efficient reaction with hexamethyldisilazane (HMDS) based on the use of I2 generated in situ from Fe(NO3)3 · 9 H2O/NaI. The reaction occurs very rapid in good-to-high yield in CH2Cl2 at room temperature, and the use of toxic and corrosive molecular I2 is avoided.
P-toluenesulfonyl chloride (p-TsCl)-catalyzed trimethylsilylation of hydroxyl groups using hexamethyldisilazane and their regeneration under mild conditions: The first example for catalytic application of p-toluenesulfonyl chloride
Khazaei, Ardeshir,Rostami, Amin,Mantashlo, Fatemeh
experimental part, p. 2288 - 2296 (2010/04/06)
The first catalytic application of p-toluenesulfonyl chloride (p-TsCl) for the efficient and selective trimethylsilylation of various types of hydroxyl groups with hexamethyldisilazane (HMDS) in dichloromethane and desilylation of these compounds in water is reported. The reactions were carried out at room temperature and were found to proceed in good to excellent yields.
Palladium-catalyzed silylation of alcohols with hexamethyldisilane
Shirakawa, Eiji,Hironaka, Koji,Otsuka, Hidehito,Hayashi, Tamio
, p. 3927 - 3929 (2007/10/03)
The combination of hexamethyldisilane and a catalytic amount of [PdCl(η3-C3H5)]2-PPh 3 was found to be effective for the trimethylsilylation of alcohols, where both of the two trimethylsilyl groups of hexamethyldisilane were transferred to alcohols without coproduction of any stoichiometric amount of byproduct but H2. The Royal Society of Chemistry 2006.
Efficient and practical protocol for silylation of hydroxyl groups using reusable lithium perchlorate dispread in silica gel under neutral condition
Azizi, Najmedin,Yousefi, Rozbeh,Saidi, Mohammad R.
, p. 817 - 820 (2007/10/03)
A very efficient and mild procedure for the trimethylsilylation of a wide variety of alcohols, including primary, allylic, benzylic, secondary, hindered secondary, tertiary, and phenols with hexamethyldisilazane on the surface of silica gel dispersed with LiClO4 in room temperature at few minutes in excellent yields under neutral conditions is reported. This procedure also allows the excellent selectivity under LP-SiO2 system for silylation of alcohols in the presence of amine and phenolic hydroxy groups.
A Convenient Method for Protection and Deprotection of Alcohols and Phenols as Alkylsilyl Ethers Catalyzed by Iodine under Microwave Irradiation
Saxena, Ira,Deka, Nabajyoti,Sarma, Jadab C.,Tsuboi, Sadao
, p. 4185 - 4191 (2007/10/03)
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.
Regioselective and Stereospecific Azidation of 1,2- and 1,3-Diols by Azidotrimethylsilane via a Mitsunobu Reaction
He, Linli,Wanunu, Meni,Byun, Hoe-Sup,Bittman, Robert
, p. 6049 - 6055 (2007/10/03)
A one-pot regio- and stereospecific azidation reaction of 1,2- and 1,3-diols with azidotrimethylsilane (MB3SiN3) via a Mitsunobu reaction has been achieved. With 1,2- and 1,3-diols, the reaction of triphenylphosphine, diisopropyl azodicarboxylate, and Me3SiN3 in dichloromethane gave regioselective azidation at C-2 and C-3, respectively, in good yield (74-90% combined yield of 1a + 1b or of 2a + 2b). However, application of the same reaction conditions to a 1,4-diol led to the exclusive formation of the cyclic ether. The regioselectivity of this one-pot reaction is influenced by the solvent, the degree of steric bulk at C-2 of the 1,2-diol or at C-3 of the 1,3-diol, and the presence of electron-donating and electron-withdrawing groups near the secondary carbinol carbon. This selectivity is discussed in terms of the mechanistic model proposed by Mathieu-Pelta and Evans (Mathieu-Pelta, I.; Evans, S. A., Jr. J. Org. Chem. 1992, 57, 3409-3413), which involves reaction of the dioxaphospholane intermediate with Me3SiN3 to form oxyphosphonium ions 4 and 5.
