Olefins oxidizing agents

Dia ene deductions. Olefins, acetylenes, and azo-compounds are reduced by hydrazine in the presence of an oxidizing agent. Stereochemical studies of alkene and alkyne reductions suggest that hydrazine is partially oxidized to the transient diazene [3618-05-1] (diimide, diimine) (9) and that the cis-isomer of diazene is the actual hydrogenating agent, acting by a concerted attack on the unsaturated bond ... 

PMMA is not affected by most inorganic solutions, mineral oils, animal oils, low concentrations of alcohols paraffins, olefins, amines, alkyl monohahdes and ahphatic hydrocarbons and higher esters, ie, >10 carbon atoms. However, PMMA is attacked by lower esters, eg, ethyl acetate, isopropyl acetate aromatic hydrocarbons, eg, benzene, toluene, xylene phenols, eg, cresol, carboHc acid aryl hahdes, eg, chlorobenzene, bromobenzene ahphatic acids, eg, butyric acid, acetic acid alkyl polyhaHdes, eg, ethylene dichloride, methylene chloride high concentrations of alcohols, eg, methanol, ethanol 2-propanol and high concentrations of alkahes and oxidizing agents. 

Reaction conditions depend on the reactants and usually involve acid or base catalysis. Examples of X include sulfate, acid sulfate, alkane- or arenesulfonate, chloride, bromide, hydroxyl, alkoxide, perchlorate, etc. RX can also be an alkyl orthoformate or alkyl carboxylate. The reaction of cycHc alkylating agents, eg, epoxides and a2iridines, with sodium or potassium salts of alkyl hydroperoxides also promotes formation of dialkyl peroxides (44,66). Olefinic alkylating agents include acycHc and cycHc olefinic hydrocarbons, vinyl and isopropenyl ethers, enamines, A[-vinylamides, vinyl sulfonates, divinyl sulfone, and a, P-unsaturated compounds, eg, methyl acrylate, mesityl oxide, acrylamide, and acrylonitrile (44,66). 

Organic Reagents. Amine oxides are used ia synthetic organic chemistry ia the preparation of olefins, or phase-transfer catalysts (47), ia alkoxylation reactions (48), ia polymerization, and as oxidizing agents (49,50). 

The hydrides can also be used to form primary alcohols from either terminal or internal olefins. The olefin and hydride form an alkenyl zirconium, Cp2ZrRCl, which is oxidized to the alcohol. Protonic oxidizing agents such as peroxides and peracids form the alcohol direcdy, but dry oxygen may also be used to form the alkoxide which can be hydrolyzed (234). 

Sulfurane reagent lor conversion of trans diols to epoxides, generally for dehydration of diols to olefins or cyclic ethers, and as an oxidizing agent... 

Used industrially as an oxidizing agent especially in conversion of olefins to glycols, and in the preparation of chlorates, peroxides, and periodates as a biological stain for adipose... 

Lastly, the radical inter- and intramolecular cyclizations in the presence of one-electron oxidizing agents as a procedure for the synthesis of five-membered cyclic nitronates can be considered. Radical oxidation of a-nitro ketones (19) in the presence of disubstituted olefins under the action of Mn(OAc)3 was documented (72a) (Scheme 3.22, Eq. 1). 

Achiral, C -symmetric unbridged metallocenes, 16 104 Achiral hydrobora ting agents, 13 667 Achiral molecules, 6 73 Acicular reinforcement, 5 554 Acid acceptors, in VDC polymer stabilization, 25 719 Acid-activated bentonites, 6 680-681 Acid amide herbicides, 13 319-320 Acid anhydrides, 10 403-406, 484 reactions with alkanolamines from olefin oxides and ammonia, 2 127 Acid-base catalysis, 5 205-209... 

The electrochemical Wacker-type oxidation of terminal olefins (111) by using palladium chloride or palladium acetate in the presence of a suitable oxidant leading to 2-alkanones (112) has been intensively studied. As recyclable double-mediatory systems (Scheme 43), quinone, ferric chloride, copper acetate, and triphenylamine have been used as co-oxidizing agents for regeneration of the Pd(II) catalyst [151]. The palladium-catalyzed anodic oxidation of... 

The reaction of superoxide ion with carbon tetrachloride is important for olefin epoxidations. This reaction includes the formation of the trichloromethyl peroxide radical Oj" + CCI4 —> Cl + CI3COO. The trichloromethyl peroxide radicals formed oxidize electron-rich olefins. The latter gives the corresponding epoxides. This peroxide radical is a stronger oxidizing agent than the superoxide ion itself (Yamamoto et al. 1986). 

The observation that the previously described diacetoxylation of olefins by means of tel-lurinic anhydrides produces quantitative yields of the corresponding ditellurides suggested the oxidative functionalization of olefins employing diphenyl diteUuride combined with an oxidizing agent instead of the tellurinic anhydride. ... 

The oxidation of organic substances by cyclic peroxides has been intensively studied over the last decades , from both the synthetic and mechanistic points of view. The earliest mechanistic studies have been carried out with cyclic peroxides such as phthaloyl peroxide , and more recently with a-methylene S-peroxy lactones and 1,2-dioxetanes . During the last 20 years, the dioxiranes (remarkable three-membered-ring cyclic peroxides) have acquired invaluable importance as powerful and mild oxidants, especially the epoxidation of electron-rich as well as electron-poor alkenes, heteroatom oxidation and CH insertions into alkanes (cf. the chapter by Adam and Zhao in this volume). The broad scope and general applicability of dioxiranes has rendered them as indispensable oxidizing agents in synthetic chemistry this is amply manifested by their intensive use, most prominently in the oxyfunctionalization of olefinic substrates. 

Diammonium hexanitratocerate (IV) (CAN) has also been used as an oxidizing agent for aldoximes. This approach is especially useful for the preparation of ahphatic 2-oxo-carbonitrile oxides (99). Another useful reagent for the generation of nitrile oxides from aldoximes is 1-chlorobenzotriazole (100). Due to its reactivity toward both aldoximes and olefins, this reagent can only be used to prepare stable... 

To prevent dimerization the concentration is kept low (10 3mol/l) but lower concentrations are allowed, when required by the bad solubility of the precursor. As an oxidizing agent 5.0 mol-% iodine in an atmosphere of air is frequently used. To prevent oxidation of the endproduct sometimes deaeration of the solvent and use of 100 mol- % iodine may be a better choice. Other useful agents are k-acceptors like tetracyanoethylene (TCNE) in dichloromethane as solvent. In most cases the helicenes are well separated from the irradiation mixture by evaporating the solvent and chromatography of the residue. In cases where the separation of the helicene and cis-olefin is difficult it is of advantage to irradiate until the olefin has completely reacted. 

We therefore employed a similar combination of catalytic Ru , with NaOCl as oxidizing agent, to the intermediate 38 to effect endocylic olefin cleavage affording dioic acid 39 (or corresponding monomethyl ester) in comparable yield, as shown in Scheme 14.12. 

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