2074-04-6Relevant academic research and scientific papers
Proton abstraction and electrophilic quench at C-2 of imidazolidines
Coldham, Iain,Judkins, Robert A.,Witty, David R.
, p. 14255 - 14264 (1998)
Imidazolidines bearing tert-butoxycarbonyl groups on both nitrogen atoms have been prepared in order to test their ability to act as acyl anion equivalents. Proton abstraction was achieved successfully at C-2, between the two nitrogen atoms, using the bas
Selective ligand-free cobalt-catalysed reduction of esters to aldehydes or alcohols
Rysak, Vincent,Descamps-Mandine, Armel,Simon, Pardis,Blanchard, Florent,Burylo, Laurence,Trentesaux, Martine,Vandewalle, Maxence,Collière, Vincent,Agbossou-Niedercorn, Francine,Michon, Christophe
, p. 3504 - 3512 (2018/07/29)
Cobalt(ii) salts combined with NaBHEt3 and eventually a base catalyse efficiently and selectively the reduction of esters to aldehydes or alcohols through hydrosilylation by using phenylsilane. Catalyst characterisation by XRD, XPS, TEM and STEM analyses indicates the materials were partially crystalline with the presence of cobalt nanoparticles. Control experiments suggested low valent Co(0) was the active catalytic species involved.
Selective Hydrosilylation of Esters to Aldehydes Catalysed by Iridium(III) Metallacycles through Trapping of Transient Silyl Cations
Corre, Yann,Rysak, Vincent,Capet, Frédéric,Djukic, Jean-Pierre,Agbossou-Niedercorn, Francine,Michon, Christophe
supporting information, p. 14036 - 14041 (2016/09/21)
The combination of an iridium(III) metallacycle and 1,3,5-trimethoxybenzene catalyses rapidly and selectively the reduction of esters to aldehydes at room temperature with high yields through hydrosilylation followed by hydrolysis. The ester reduction involves the trapping of transient silyl cations by the 1,3,5-trimethoxybenzene co-catalyst, supposedly by formation of an arenium intermediate whose role was addressed by DFT calculations.
Hypoiodite-catalyzed regioselective oxidation of alkenes: An expeditious access to aldehydes in aqueous micellar media
Swamy, Peraka,Reddy, Marri Mahender,Naresh, Mameda,Kumar, Macharla Arun,Srujana, Kodumuri,Durgaiah, Chevella,Narender, Nama
supporting information, p. 1125 - 1130 (2015/04/22)
A highly anti-Markovnikov selective oxidation of alkenes based on in situ generated hypoiodite catalysis in aqueous micellar media under mild conditions has been described. This novel catalytic system realizes an efficient synthesis of aldehydes from alkenes in an economically viable and environmentally safe fashion. The preliminary mechanistic studies suggest that the reaction proceeds via tandem iodofunctionalization/1,2-aryl or alkyl migration. The scope and limitations of this tandem process are demonstrated with various mono- and disubstituted (terminal and internal) olefins.
2-Iodoxybenzoic acid organosulfonates: Preparation, X-ray structure and reactivity of new, powerful hypervalent iodine(v) oxidants
Yusubov, Mekhman S.,Svitich, Dmitrii Yu.,Yoshimura, Akira,Nemykin, Victor N.,Zhdankin, Viktor V.
supporting information, p. 11269 - 11271 (2013/12/04)
New powerful hypervalent iodine(v) oxidants, tosylate and mesylate derivatives of 2-iodoxybenzoic acid (IBX), were prepared by the reaction of IBX with the corresponding sulfonic acids. Single crystal X-ray crystallography of the diacetate derivative of IBX-tosylate revealed an unusual heptacoordinated iodine geometry without any significant intermolecular secondary interactions.
Efficient and highly aldehyde selective wacker oxidation
Teo, Peili,Wickens, Zachary K.,Dong, Guangbin,Grubbs, Robert H.
supporting information; experimental part, p. 3237 - 3239 (2012/08/27)
A method for efficient and aldehyde-selective Wacker oxidation of aryl-substituted olefins using PdCl2(MeCN)2, 1,4-benzoquinone, and t-BuOH in air is described. Up to a 96% yield of aldehyde can be obtained, and up to 99% selectivity can be achieved with styrene-related substrates.
CATALYTIC ANTI-MARKOVNIKOV OXIDATION AND HYDRATION OF OLEFINS
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Page/Page column 19-20, (2012/07/14)
The disclosure provides a dual-catalysis system for direct conversion of olefins to alcohols. The cooperative catalytic system contains one oxidizing catalyst and one transfer-hydrogenation catalyst. A wide variety of olefins, including aromatic and aliphatic olefins, can be used as the reactant. The transformation proceeds with anti-Markovnikov selectivity, and in some aspects provides primary alcohols as major products. The disclosure further provides a system for oxidation of olefins with anti-Markovnikov selectivity.
Halonium ion-assisted deiodination of styrene-based vicinal iodohydrins followed by rearrangement through phenyl migration
Agrawal, Manoj K.,Ghosh, Pushpito K.
experimental part, p. 7947 - 7950 (2010/01/16)
(Chemical Equation Presented) Acid activation of bromate/bromide couple at 0-10°C was found to trigger the deiodination of styrene-based vicinal iodohydrins. Violet coloration of the organic layer was ascribed to formation of IBr. Deiodination was followed by phenyl migration and deprotonation leading to formation of phenyl acetone and 2-phenylpropanal in good yields from 1-iodo-2-phenylpropan-2-ol and 2-iodo-1-phenylpropan-1-ol, respectively. Phenyl acetaldehyde-which was obtained in 92% GC yield from styrene iodohydrin-was also presumably formed in analogous manner. NBS and HOCl too were effective for transformation of styrene iodohydrin into phenyl acetaldehyde. 2009 American Chemical Society.
Oligomeric iodosylbenzene sulfate: A convenient hypervalent iodine reagent for oxidation of organic sulfides and alkenes
Yusubov, Mehman S.,Yusubova, Rosa Y.,Funk, Tatyana V.,Chi, Ki-Whan,Zhdankin, Viktor V.
experimental part, p. 2505 - 2508 (2009/12/08)
Oligomeric iodosylbenzene sulfate, (PhIO)3·SO 3, which can be formally considered as a partially depolymerized activated iodosylbenzene, is a readily available, stable, and water-soluble hypervalent iodine reagent that is useful for the oxidation of sulfides or alkenes. Furthermore, this reagent can be conveniently generated in situ from (diacetoxyiodo)benzene and sodium bisulfate and used without isolation in oxidations in aqueous solution or under solvent-free conditions. The reaction of iodosylbenzene sulfate in situ with organic sulfides at room temperature affords sulfoxides in high yields without over-oxidation to sulfones, and this reaction is compatible with the presence in the substrate molecule of hydroxy groups, double bonds, benzylic carbon atoms, carboxylate groups, and various substituted phenyl rings. The reaction of an alkene with iodosylbenzene sulfate generated in situ results in oxidative rearrangement to form a ketone or aldehyde. Georg Thieme Verlag Stuttgart.
m-iodosylbenzoic acid as a convenient recyclable reagent for highly efficient RuCl3-catalyzed oxidation of alcohols to carbonyl compounds
Yusubov, Mekhman S.,Gilmkhanova, Marina P.,Zhdankin, Viktor V.,Kirschning, Andreas
, p. 563 - 566 (2007/10/03)
m-Iodosylbenzoic acid selectively oxidizes primary and secondary alcohols to the respective carbonyl compounds in the presence of RuCl3 (0.5 mol%) at room temperature in aqueous acetonitrile. Separation of pure products is conveniently achieved by scavenging any aryl iodide by ion exchange with IRA-900 (hydroxide form) or by simple extraction of the basic aqueous solution with water. The reduced form of the reagent, m-iodobenzoic acid, can be easily recovered from the ion-exchange resin or from the basic aqueous solution by simple acidification with HCl. Georg Thieme Verlag Stuttgart.
