Synthetic methods and reactions 104. Silylations with in situ generated trimethylsilyl triflate reagent systems

Abstract

lithium jV-phthaloyl-L-phenylalaninate, 79069-04-8; l,2:5,6-di-0-isopropylidene-3-C-methylene-a-D-ribohexofuranose, 21665-16-7; l,2:5,6-di-0-isopropylidene-3-deoxy-3-oxo-a-D-ribohexofuranose, 2847-00-9; 2',3'-0-isopropylideneuridine, 362-43-6. Notes Synthetic Methods and Reactions. 104.1

Silicon‐Assisted Direct Covalent Grafting on Metal Oxide Surfaces: Synthesis and Characterization of Carboxylate N,N′‐Ligands on TiO2

“…Trimethylsilylation of carboxylic acids can be accomplished with various trimethylsilyl blocking agents such as chlorotrimethyl-, [44] cyano-, [45] isopropenoxy-, [46] or allylsilanes [47] . The choice for the present study was bis(trimethylsilyl)urea, [48] based on stability, toxicity, and reactivity factors.…”

Highly efficient chemo- and regioselective silylation of –OH groups and cyanosilylation of aldehydes promoted by TiCl2(OTf)–SiO2 as a new recyclable catalyst

“…Preparation of silyl ethers from allylsilane and silyl enol ethers in the presence of catalytic amount of p-toluenesulfonic acid [8,9], I 2 [10], trifluoromethanesulfonic acid [11] or Sc(OTf) 3 [12] are also appeared in the literature. Although these procedures provide improvements, they suffer from expensive silylating agents and catalysts, using hazardous and not available chemicals such as DEAD, moisture sensitive compounds and using organic solvents.…”

Iron(III) trifluoroacetate [Fe(F3CCO2)3] as an easily available, non-hygroscopic, non-corrosive, highly stable and a reusable Lewis Acid catalyst: Efficient O-silylation of α-hydroxyphosphonates, alcohols and phenols by hexamethyldisilazane (HMDS) under solvent-free conditions

“…This transformation enhances solubility in non-polar solvents, increases thermal stability and in addition trimethylsilylation of hydroxyl compounds is used extensively to increase volatility of the compounds for gas chromatography and mass spectrometry as well. Several methods have been reported for this aim, including the reaction of an alcohol with trimethylsilyl halides in the presence of stoichiometric amount of a tertiary amine [4,5], with trimethylsilyl triflate, which is more reactive than the chloride [6], with R 3 Si-H activated by dirhodium(II) perfluorooctanoate [Rh 2 (PFO) 4 ] [7], with Ph 2 P-SiEt 3 in the presence of diethyl azodicarboxylate (DEAD)/pyridinium p-toluenesulfonate (PPTS) [8], with allylsilanes in the presence of catalytic amounts of p-toluenesulfonic acid [9], iodine [10], trifluoromethanesulfonic acid [11], or Sc(OTf) 3 [12], (Me 3 Si) 2 catalyzed by PdCl(g 3 -C 3 H 5 ) 2 /PPh3 [13]. Some of these methods suffer from use of expensive silylating agents and catalysts, using hazardous chemicals such as DEAD and also not easily available reagents or catalysts and highly moisture sensitive compounds [6][7][8].…”