15251-78-2Relevant academic research and scientific papers
Enantioselective Aromatic Sulfide Oxidation and Tandem Kinetic Resolution Using Aqueous H2O2 and Chiral Iron–Bis(oxazolinyl)bipyridine Catalysts
Jalba, Angela,Régnier, Noémie,Ollevier, Thierry
, p. 1628 - 1637 (2017/04/06)
An efficient method for the oxidation of aromatic sulfides has been developed by using aqueous H2O2, catalyzed by the in situ generated chiral Fe/6,6′-bis(4-isopropyloxazolin-2-yl)-2,2′-bipyridine (bipybox-iPr) complex. The corresponding sulfoxides were obtained with high enantioselectivities (up to 98.5:1.5 er) and in good yields (up to 61 %) when the mono-oxidation of the sulfides was performed in combination with the kinetic resolution of the sulfoxide into the sulfone.
Total Synthesis of rapamycin
Ley, Steven V.,Tackett, Miles N.,Maddess, Matthew L.,Anderson, James C.,Brennan, Paul E.,Cappi, Michael W.,Heer, Jag P.,Helgen, Celine,Kori, Masakuni,Kouklovsky, Cyrille,Marsden, Stephen P.,Norman, Joanne,Osborn, David P.,Palomero, Maria A.,Pavey, John B. J.,Pinel, Catherine,Robinson, Lesley A.,Schnaubelt, Juergen,Scott, James S.,Spilling, Christopher D.,Watanabe, Hidenori,Wesson, Kieron E.,Willis, Michael C.
experimental part, p. 2874 - 2914 (2009/12/25)
For over 30 years, rapamycin has generated a sustained and intense interest from the scientific community as a result of its exceptional pharmacological properties and challenging structural features. In addition to its well known therapeutic value as a potent immunosuppressive agent, rapamycin and its derivatives have recently gained prominence for the treatment of a wide variety of other human malignancies. Herein we disclose full details of our extensive investigation into the synthesis of rapamycin that culminated in a new and convergent preparation featuring a macro-etherification/catechol-templating strategy for construction of the macrocyclic core of this natural product.
Chromium(VI) oxide catalyzed oxidation of sulfides to sulfones with periodic acid
Xu, Liang,Cheng, Jie,Trudell, Mark L.
, p. 5388 - 5391 (2007/10/03)
A highly efficient and selective oxidation of sulfides to sulfones with periodic acid catalyzed by CrO3 is described. A variety of electron-rich and electron-deficient sulfides were oxidized to sulfones with 2 mol% CrO3 in acetonitrile at room temperature in excellent yields. Sulfides with other readily oxidized functional groups were selectively oxidized to sulfones in high yields with 10 mol% CrO3 in ethyl acetate/acetonitrile at -35 °C.
Solvent free permanganate oxidations
Shaabani, Ahmad,Lee, Donald G.
, p. 5833 - 5836 (2007/10/03)
The oxidations of organic compounds by permanganate under solvent free conditions have been studied. Thiols and primary aromatic amines undergo oxidative coupling reactions to give disulfides and diazenes, respectively, sulfides are oxidized to sulfones, primary and secondary alcohols are converted to aldehydes and ketones, 1,4-diols and cyclic ethers give lactones and arenes are oxidized to the corresponding α-ketones. The experimental procedure is simple and the products are easily isolated in good yields.
Oxidation of Sulfur-Containing Compounds with HOF-CH3CN
Rozen, Shlomo,Bareket, Yifat
, p. 1457 - 1462 (2007/10/03)
The HOF-CH3CN complex, easily prepared by passing F2 through aqueous acetonitrile, is an exceptionally efficient oxygen transfer agent. All types of sulfides have been oxidized to sulfones in excellent yields, in a few minutes at room temperature. The reaction proceeds through the formation of sulfoxides which at low temperatures of around -75°C could be isolated in good yields. It was demonstrated through a reaction with thianthrene 5-oxide (20) that HOF·CH3CN is strongly electrophilic in nature. Sulfides with an electron-depleted sulfur atom such as perfluoroalkyl or aryl sulfides, which could not be well oxidized by any other method, were also efficiently converted to the corresponding sulfones in minutes. Thiophenes are generally hard to oxidize to the corresponding S-dioxides since the conditions required by the orthodox oxidants encourage consecutive typical ene and diene reactions. HOF·CH3CN requires short reaction times and low temperatures, thus enabling the isolation of thiophene dioxides, some of which could not be made by any other way. It seems that apart from unprotected amines, other functional groups such as aromatic rings, ketones, hydroxyls, and ethers do not interfere, since the sulfur atom reacts considerably faster.
Ketone homologation to produce α-methoxyketones: Application to conduritol synthesis
Phillipson, Neil,Anson, Michael S.,Montana, John G.,Taylor, Richard J. K.
, p. 2821 - 2829 (2007/10/03)
The scope of Trost's sulfone homologation procedure for the conversion of ketones into their α-methoxylated higher homologues has been dramatically expanded. The use of zirconium (or hafnium) tetrachloride in the hydroxy sulfone rearrangement step gives g
Towards the Synthesis of the C37-C42 Fragment of Rapamycin: Intramolecular Reactions of Allyl Silanes with Oxonium Ions Generated from α-Alkoxy Sulfones.
Ley, Steven V.,Kouklovsky, Cyrille
, p. 835 - 848 (2007/10/02)
A new method for the formation of methylene cyclohexane derivatives has been developed, using intramolecular trapping by allyl silanes of oxonium ions generated from α-alkoxysulfones.These acyclic precursors were prepared by quenching the anion of methoxy
Sulfur Heterocycles. 3. Heterogeneous, Phase-Transfer, and Acid-Catalyzed Potassium Permanganate Oxidation of Sulfides to Sulfones and a Survey of their Carbon-13 Nuclear Magnetic Resonance Spectra
Gokel, George W.,Gerdes, Harold M.,Dishong, Dennis M.
, p. 3634 - 3639 (2007/10/02)
Although numerous oxidation methods are available for the transformation of sulfides into sulfones, low-molecular-weight, heterocyclic sulfides are often not amenable to this oxidation techniques.The method presented here is a general and economical oxidation using potassium permanganate and various catalysts.Nineteen low-molecular-weight and heterocyclic sulfides were successfully oxidized by variations of this technique, and the results are presented here.In addition, the carbon-13 NMR spectra of these compounds and about two dozen others are reported.General chemical shift trends are reported for selected compounds, and details can be found in the supplementary material.
