119-60-8Relevant articles and documents
S,S-dimethyl dithiocarbonate: A novel carbonyl dication synthon in the synthesis of ketones
Chen, Chiar-Dy,Huang, Jui-Wen,Leung, Man-Kit,Li, Huei-Hsu
, p. 9067 - 9078 (1998)
We report herein the use of DMDTC as an effective carbonyl dication equivalent in ketone synthesis. According to our strategy, we also successfully devised a synthetic pathway for S-methyl (trimethylsilyl)thioacetate which may be a potentially useful synthetic reagent in organic synthesis.
Synthesis and characterization of alkyl-imidazolium-based periodic mesoporous organosilicas: A versatile host for the immobilization of perruthenate (RuO4-) in the aerobic oxidation of alcohols
Karimi, Babak,Elhamifar, Dawood,Yari, Omolbanin,Khorasani, Mojtaba,Vali, Hojatollah,Clark, James H.,Hunt, Andrew J.
, p. 13520 - 13530 (2012)
The preparation and characterization of a set of periodic mesoporous organosilicas (PMOs) that contain different fractions of 1,3-bis(3- trimethoxysilylpropyl)imidazolium chloride (BTMSPI) groups uniformly distributed in the silica mesoporous framework is described. The mesoporous structure of the materials was characterized by powder X-ray diffraction, transmission electron microscopy, and N2 adsorption-desorption analysis. The presence of propyl imidazolium groups in the silica framework of the materials was also characterized by solid-state NMR spectroscopy and diffuse-reflectance Fourier-transform infrared spectroscopy. The effect of the BTMSPI concentration in the initial solutions on the structural properties (including morphology) of the final materials was also examined. The total organic content of the PMOs was measured by elemental analysis, whereas their thermal stability was determined by thermogravimetric analysis. Among the described materials, it was found that PMO with 10 % imidazolium content is an effective host for the immobilization of perruthenate through an ion-exchange protocol. The resulting Ru@PI-10 was then employed as a recyclable catalyst in the highly efficient aerobic oxidation of various types of alcohols.
Site-selective oxidation, amination and epimerization reactions of complex polyols enabled by transfer hydrogenation
Hill, Christopher K.,Hartwig, John F.
, p. 1213 - 1221 (2017)
Polyoxygenated hydrocarbons that bear one or more hydroxyl groups comprise a large set of natural and synthetic compounds, often with potent biological activity. In synthetic chemistry, alcohols are important precursors to carbonyl groups, which then can be converted into a wide range of oxygen- or nitrogen-based functionality. Therefore, the selective conversion of a single hydroxyl group in natural products into a ketone would enable the selective introduction of unnatural functionality. However, the methods known to convert a simple alcohol, or even an alcohol in a molecule that contains multiple protected functional groups, are not suitable for selective reactions of complex polyol structures. We present a new ruthenium catalyst with a unique efficacy for the selective oxidation of a single hydroxyl group among many in unprotected polyol natural products. This oxidation enables the introduction of nitrogen-based functional groups into such structures that lack nitrogen atoms and enables a selective alcohol epimerization by stepwise or reversible oxidation and reduction.
C(sp3)-H Bond Acylation with N -Acyl Imides under Photoredox/ Nickel Dual Catalysis
Kerackian, Taline,Reina, Antonio,Krachko, Tetiana,Boddaert, Hugo,Bouyssi, Didier,Monteiro, Nuno,Amgoune, Abderrahmane
, p. 1531 - 1536 (2021)
A novel Ni/photoredox-catalyzed acylation of aliphatic substrates, including simple alkanes and dialkyl ethers, has been developed. The method combines C-N bond activation of amides with a radical relay mechanism involving hydrogen-atom transfer. The protocol is operationally simple, employs bench-stable N -acyl imides as acyl-transfer reagents, and permits facile access to alkyl ketones under very mild conditions.
Synthesis of Dialkyl Ketones from Alkenes Using Ph(Et)2N:BH3/CoCl2/CO Reagent System
Rao, Maddali L. N.,Periasamy, Mariappan
, p. 9069 - 9070 (1995)
Reaction of alkenes with Ph(Et)2N:BH3/CoCl2/Co in THF followed by oxidation gives the corresponding dialkyl ketones.
Nucleophilic reactivity of a copper(II)-superoxide complex
Pirovano, Paolo,Magherusan, Adriana M.,McGlynn, Ciara,Ure, Andrew,Lynes, Amy,McDonald, Aidan R.
, p. 5946 - 5950 (2014)
Metal-bound superoxide intermediates are often implicated as electrophilic oxidants in dioxygen-activating metalloenzymes. In the nonheme iron α-ketoglutarate dependent oxygenases and pterin-dependent hydroxylases, however, FeIII-superoxide intermediates are postulated to react by nucleophilic attack on electrophilic carbon atoms. By reacting a Cu II-superoxide complex (1) with acyl chloride substrates, we have found that a metal-superoxide complex can be a very reactive nucleophile. Furthermore, 1 was found to be an efficient nucleophilic deformylating reagent, capable of Baeyer-Villiger oxidation of a number of aldehyde substrates. The observed nucleophilic chemistry represents a new domain for metal-superoxide reactivity. Our observations provide support for the postulated role of metal-superoxide intermediates in nonheme iron α-ketoglutarate dependent and pterin-dependent enzymes. Nucleophilic superoxide: A copper(II)-superoxide complex has been found to be a highly reactive nucleophile. The complex reacts readily with certain electrophiles and is capable of the nucleophilic deformylation of electron-rich aldehydes (Baeyer-Villiger oxidation). These observations provide experimental support for the postulated nucleophilic reactivity of metal-superoxide intermediates in the catalytic cycles of certain nonheme iron enzymes.
Diisopropyloxy(η2-cyclopentene)titanium for the diastereoselective synthesis of various 1,2-disubstituted cyclopentanes
Cadoret, Frédéric,Retailleau, Pascal,Six, Yvan
, p. 7749 - 7753 (2006)
The reaction of 3 equiv of cyclopentylmagnesium chloride with 2 equiv of titanium(IV) isopropoxide at low temperature (-70 to -50 °C) leads to the formation of 1 equiv of diisopropyloxy(η2-cyclopentene)titanium containing low amounts of the starting Grignard reagent. The sequential addition of two electrophiles onto this titanium complex involved as an intermediate in Kulinkovich-type reactions delivers various 1,2-disubstituted cyclopentane rings with generally high diastereoselectivity. Mechanistic considerations and possible extensions of this method are discussed.
Electrochemistry Broadens the Scope of Flavin Photocatalysis: Photoelectrocatalytic Oxidation of Unactivated Alcohols
Zhang, Wen,Carpenter, Keith L.,Lin, Song
, p. 409 - 417 (2020)
Riboflavin-derived photocatalysts have been extensively studied in the context of alcohol oxidation. However, to date, the scope of this catalytic methodology has been limited to benzyl alcohols. In this work, mechanistic understanding of flavin-catalyzed oxidation reactions, in either the absence or presence of thiourea as a cocatalyst, was obtained. The mechanistic insights enabled development of an electrochemically driven photochemical oxidation of primary and secondary aliphatic alcohols using a pair of flavin and dialkylthiourea catalysts. Electrochemistry makes it possible to avoid using O2 and an oxidant and generating H2O2 as a byproduct, both of which oxidatively degrade thiourea under the reaction conditions. This modification unlocks a new mechanistic pathway in which the oxidation of unactivated alcohols is achieved by thiyl radical mediated hydrogen-atom abstraction.
Synthesis of Ketones and Tertiary Alcohols from Trialkylboranes. Use of Lithium Tris(phenylthio)methanide
Pelter, Andrew,Rao, J. Madhusudhana
, p. 1149 - 1150 (1981)
The interaction of lithium tris(phenylthio)methanide with trialkylboranes followed by oxidation allows the production of ketones or tertiary alcohols in good yields under mild conditions.
PET-oxidative cyclization of unsaturated enol silyl ethers
Heidbreder, Andreas,Mattay, Jochen
, p. 1973 - 1976 (1992)
Unsaturated enol silyl ethers are irradiated in the presence of the electron transfer sensitizer 9, 10-dicyanoanthracene to form silyloxy radical cations which cyclize efficiently to yield cyclic ketones. Cyclization reactions of ε,ζ-unsaturated enol silyl ethers lead exclusively to 6-membered rings.
