28567-36-4Relevant academic research and scientific papers
Highly efficient protection of alcohols as trityl ethers under solvent-free conditions, and recovery catalyzed by reusable nanoporous MCM-41-SO3H
Gholamzadeh, Zeynab,Naimi-Jamal, Mohammad Reza,Maleki, Ali
, p. 994 - 1001 (2015/01/09)
An efficient method was developed for the protection of alcohols as trityl ethers using triphenylmethanol in the presence of nanoporous MCM-41-SO3H as a heterogeneous catalyst under solvent-free ball-milling at room temperature. Low catalyst loading, high efficiency, reusability are among the advantages of this new solvent-free and environmentally friendly method. The deprotection of the produced trityl ethers was also efficiently achieved using the same catalyst in wet acetonitrile.
Zinc chloride homogeneous catalysis in the tritylation of hydroxyl- and amide-bearing molecules
Maltese, Maurizio,Vergari, Maria Cecilia,Donzello, Maria Pia
supporting information; experimental part, p. 483 - 487 (2011/03/18)
A tritylation protocol based on the transfer of the triphenylmethylcarbenium ion from trityl acetate to substrates having hydroxyls, in the presence of catalytic amounts of ZnCl2, is described. The advantages of this method are broad scope, mild conditions, and easy handling. The comparison with the procedure based on the use of equimolar mixture of TrCl and ZnCl2 in the presence of TEA shows that comparable results are obtained. However, only this method allows reactions of secondary or benzylic alcohols such as oxidation or formation of symmetric ethers to be suppressed. Both procedures are successfully extended to simple and substituted amides. Irrespective of its low solubility in acetonitrile, even asparagine can be directly tritylated on its amide group.
FeCl3-catalyzed tritylation of alcohols in ionic liquids
Sreedhar,Radhika,Neelima,Chowdary,Rao, M. V. Basaveswara
experimental part, p. 3785 - 3795 (2009/12/08)
A simple and efficient protection of alcohols as trityl ethers is described using trityl chloride in the presence of 5mol% FeCl3 as catalyst in ionic liquids at room temperature in shorter reaction times. This mild and efficient method gives access to the
Transformation of Carbinols by RuCl2(PPh3)3 and by Some Other Transition-Metal Catalysts
Pri-Bar, Ilan,Buchman, Ouri,Schumann, Hebert,Kroth, Heinz J.,Blum, Jochanan
, p. 4418 - 4428 (2007/10/02)
Several platinoid metal catalysts have been shown to promote reductive coupling, dehydration, disproportionation, and dehydrogenation of diarylcarbinols.Mechanistic studies were performed at 180-210 deg C with benzhydrol as substrate and RuCl2(PPh3)3 as catalyst.In aromatic hydrocarbon solvents the main process is reductive coupling.In this medium solvated RuCl2(PPh3)2 is suggested to be the active catalyst.In dimethyl sulfoxide the starting complex is transformed initially into RuCl2(PPh3)(Me2SO)2 and causes chiefly carbinol dehydrogenation.Ruthenium alkoxides are implied as common reaction intermediates in all four catalyses.Ruthenium hydrides are suggested to take part in the reductive coupling, disproportionation, and dehydrogenation processes.Some aliphatic and primary aromatic alcohols that do not react by themselves in the presence of RuCl2(PPh3)3 can both serve as active hydrogen donors and form crossover products in the presence of secondary and tertiary aromatic carbinols.
