112-12-9Relevant articles and documents
Selective oxidation of alcohols to carbonyl compounds mediated by fluorous-tagged TEMPO radicals
Holczknecht, Orsolya,Cavazzini, Marco,Quici, Silvio,Shepperson, Ian,Pozzi, Gianluca
, p. 677 - 688 (2005)
Oxidation of primary, benzylic and secondary alcohols into their corresponding aldehydes and ketones with safe, inexpensive oxidants was achieved in good yields under mild conditions in the presence of catalytic amounts of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) radicals bearing perfluoroalkyl substituents. These "fluorous-tagged" TEMPOs were readily isolated from the reaction products by liquid-liquid or solid-phase extraction, considerably simplifying the purification step. Their recyclability was strongly influenced by the nature of the oxidizing system. The best results were obtained using either [bis(acetoxy)iodo]benzene (BAIB) or aqueous NaOCl as the primary oxidants. Fluorous TEMPO 10 could be reused up to six times in the BAIB oxidation of 1-octanol with only minor loss of catalytic activity.
Imidazolium Dichromate. A New Reagent for the Oxidation of Alcohols to Carbonyl Compounds
Kim, Sunggak,Lhim, Dong Chul
, p. 3297 - 3298 (1986)
Imidazolium dichromate, a stable yellow crystalline compound, is found to bee a mild selective reagent for the oxidation of allylic and benzylic alcohols to the corresponding carbonyl compounds.
Thaler,Staehlin
, p. 86 (1949)
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Allen,J.C. et al.
, p. 4468 - 4475 (1962)
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Takeda,Mukaiyama
, p. 477 (1976)
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Deprotection of dithioacetals using the tantalum(V) chloride catalyzed oxidation of iodide ion by hydrogen peroxide
Kirihara, Masayuki,Harano, Aiko,Tsukiji, Hiroyuki,Takizawa, Ryu,Uchiyama, Tomoyuki,Hatano, Akihiko
, p. 6377 - 6380 (2005)
Dithioacetals can be deprotected to afford carbonyl groups using the tantalum(V) chloride catalyzed oxidation of iodide ion by hydrogen peroxide under mild conditions.
Synthesis and catalytic activity of a fluorous-tagged TEMPO radical
Pozzi, Gianluca,Cavazzini, Marco,Holczknecht, Orsolya,Quici, Silvio,Shepperson, Ian
, p. 4249 - 4251 (2004)
A fluorous-tagged TEMPO radical has been prepared and its catalytic activity in the chemoselective oxidation of alcohols to carbonyl compounds has been investigated. The new fluorous radical proved to be an efficient, selective and easily recoverable catalyst, which can be conveniently used in standard organic solvents and then isolated and recycled by fluorous liquid-liquid extraction.
Copper-catalyzed aerobic oxidation of alcohols under fluorous biphasic conditions
Betzemeier, Bodo,Cavazzini, Marco,Quici, Silvio,Knochel, Paul
, p. 4343 - 4346 (2000)
A catalytic amount of perfluoroalkyl substituted bipyridine 1 (2 mol%), CuBr·Me2S (2 mol%) and TEMPO (3.5 mol%) allow the oxidation of various alcohols to aldehydes and ketones in a fluorous biphasic system of chlorobenzene and perfluorooctane directly with oxygen. The catalyst can be used for several reaction runs without a loss of reactivity. (C) 2000 Elsevier Science Ltd.
Poly(ethylene glycol)-supported nitroxyls: Branched catalysts for the selective oxidation of alcohols
Ferreira, Pedro,Phillips, Emyr,Rippon, David,Shik, Chi Tsang,Hayes, Wayne
, p. 6851 - 6859 (2004)
Nitroxyl radicals such as 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) are highly selective oxidation catalysts for the conversion of primary alcohols into the corresponding aldehydes. In this study, direct tethering of TEMPO units onto linear poly(ethylene glycol) (PEG) has afforded macromolecular catalysts that exhibit solubility in both aqueous and organic solvents. Recovery of the dissolved polymer-supported catalyst has been carried out by precipitation with a suitable solvent such as diethyl ether. The high catalyst activities and selectivities associated traditionally with nitroxyl-mediated oxidations of alcohols are retained by the series of "linker-less" linear PEG-TEMPO catalysts in which the TEMPO moiety is coupled directly to the PEG support. Although the selectivity remains unaltered, upon recycling of the linker-less polymer-supported catalysts, extended reaction times are required to maintain high yields of the desired carbonyl compounds. Alternatively, attachment of two nitroxyl radicals onto each functionalized PEG chain terminus via a 5-hydroxyisophthalic acid linker affords branched polymer-supported catalysts. In stark contrast to the linker-less catalysts, these branched nitroxyls exhibit catalytic activities up to five times greater than 4-methoxy-TEMPO alone under similar conditions. In addition, minimal decrease in catalytic activity is observed upon recycling of these branched macromolecular catalysts via solvent-induced precipitation. The high catalytic activities and preservation of activity upon recycling of these branched systems is attributed to enhanced regeneration of the nitroxyl species as a result of intramolecular syn-proportionation.
Copper(I)- and Mesoionic-Hydroxyamide-Catalyzed Chemoselective Aerobic Oxidation of Primary Benzylic Alcohols
Matsukawa, Yuta,Hirashita, Tsunehisa
, p. 315 - 318 (2019)
A new aerobic oxidation system consisting of Cu(I)I, 2,2'-bipyridine, N -methyl imidazole, and a mesoionic hydroxyamide was developed, with which selective oxidation of a broad range of benzylic alcohols was achieved.
Electrochemical generation of cationic Pd catalysts and application to Pd/TEMPO double-mediatory electrooxidative Wacker-type reactions
Mitsudo, Koichi,Kaide, Takashi,Nakamoto, Eriko,Yoshida, Kenta,Tanaka, Hideo
, p. 2246 - 2247 (2007)
We have developed an electrooxidative method for generating cationic palladium complexes [Pd(CH3CN)4][X]2 (X = BF4, PF6, and ClO4) from Pd(OAc)2 and several electrolytes bearing X groups in CH3CN. The system could be integrated into an electrochemical Wacker-type reaction. In the presence of a catalytic amount of TEMPO, the reaction proceeded smoothly to give the corresponding methyl ketones. Copyright
Indirect Electrooxidation of Alcohols by a Double Mediatory System with Two Redox Couples of +=O>/R2NO. and . or Br+>/Br- in an Organic-Aqueous Two-Phase Solution
Inokuchi, Tsutomu,Matsumoto, Sigeaki,Torii, Sigeru
, p. 2416 - 2421 (1991)
An indirect electrooxidation method for alcohol to aldehyde or ketone conversion has been developed.This method, applicable to chemoselective oxidation, employs two redox couples, consisting of 2,2,6,6-tetramethylpiperidine-1-oxyl derivatives 6 and active bromine species.The former is required for the chemical process and recycled, whereas the latter is to be involved in the electrochemical process.Three chemical events play an important role in this system: (1) the formation of . or Br+> from bromide ion by discharge on the anode in an aqueous solution, (2) the reaction of N-oxyl compounds 6 with active bromine species to generate N-oxoammonium ion 7, and (3) the oxidation of alcohols with 7 in an organic phase.Optimum conditions were established as follows: an aqueous 25percent NaBr solution buffered at pH 8.6 in a binary system, the use of 1-10 mol percent of 4-(benzoyloxy)piperidine derivatives 6, and adjustment of an electric current at 10-100 mA/cm2.The successful applications of the present method to the oxidation of a variety of primary and secondary alcohols including 1,n-diols, giving the corresponding carbonyl compounds, have delineated its synthetic utility.The chemoselective oxidation of a primary hydroxy group in the presence of secondary one has been achieved with a high selectivity by the present procedure.
Efficient One-Pot Multifunctionalization of Alkynes en Route to α-Alkoxyketones, α-Thioketones, and α-Thio Thioketals by using an Umpolung Strategy
Xu, Zhou,Zhai, Rongliang,Liang, Ting,Zhang, Liming
, p. 14133 - 14137 (2017)
The use of polarized synthons is a highly desirable strategy, as it generally enables unprecedented retrosynthetic disconnections for the synthesis of unique substances. Herein, a new approach for α-oxygenated ketones, α-thioketones and α-thio thioketals via an intermolecular umpolung reaction between nucleophiles (alcohols/thioalcohols) and N-alkenoxypyridinium salts, which were generated from the corresponding alkynes, has been developed for the first time. The reactions proceed with good substrate scope and excellent functional group tolerance in one-pot manner. Applications of the products, α-oxygenated ketones, to the synthesis of other valuable synthetic moieties has also been successfully achieved.
Electrochemical Wacker Type Reaction with a Double Mediatory System Consisting of Palladium Complex and Tri(4-bromophenyl)amine
Inokuchi, Tsutomu,Ping, Liu,Hamaue, Fumihiro,Izawa, Miyoko,Torii, Sigeru
, p. 121 - 124 (1994)
The electrochemical Wacker type oxidation of terminal olefins by using palladium chloride or palladium acetate and tri(4-bromophenyl)amine as a recyclable mediator in either a divided cell or an undivided cell afforded the corresponding methyl ketones in good yields.
A BIOMIMETIC SYNTHESIS OF (+/-)-NANAOMYCIN A
Yamaguchi, Masahiko,Nakamura, Shigeo,Okuma, Tadashi,Minami, Toru
, p. 3913 - 3916 (1990)
A biosynthetic intermediate of isochromanequinone antibiotics was synthesized, and biomimetically converted to (+/-)-nanaomycin A.A novel synthetic method of methyl ketones from esters was also developed.
Preparation method of (cyclic)alkyl acetone
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Paragraph 0025; 0026, (2020/01/08)
A purpose of the invention is to provide a preparation method of (cyclic)alkyl acetone. The preparation method specifically comprises: sequentially adding acetic acid, potassium acetate, manganese acetate, acetic anhydride and acetone into a reaction flask, heating to a reaction temperature, adding olefin and an oxidant, and carrying out a free radical addition reaction represented by the following formula 2 at a reaction temperature of 30-100 DEG C to obtain (cyclic) alkyl acetone represented by a formula 2. According to the present invention, the preparation method is simple and safe to operate, and low in production cost.
Nitrosotetrazolium-Catalyzed Aerobic Oxidation of Alcohols to the Corresponding Carbonyl Compounds
Matsukawa, Yuta,Hirashita, Tsunehisa,Araki, Shuki
, p. 1359 - 1363 (2018/04/02)
A mesoionic-nitrosotetrazolium-catalyzed aerobic oxidation of alcohols is reported. In the presence of catalytic amounts of 5-nitroso-1,3-diphenyltetrazolium tetrafluoroborate (5 mol-%) and nitric acid (20 mol-%), a wide range of alcohols are oxidized to the corresponding aldehydes and ketones in yields of 53–100 % at room temperature under ambient air or oxygen conditions. This oxidation shows a strong preference for secondary alcohols over primary alcohols; sterically hindered alcohols are also smoothly oxidized. A mechanism involving a nitroso/NOx catalytic cycle is proposed.