By oxidation, with hydrogen peroxide

The formation of trisubstituted A-4 thiazoline-2-ones from the corresponding thiones analogs can be performed by oxidation with hydrogen peroxide under basic conditions. This reaction is strongly dependent on the pH of the medium. Higher yields are obtained in strongly alkaline solution (883). 

Methylsuccinic acid has been prepared by the pyrolysis of tartaric acid from 1,2-dibromopropane or allyl halides by the action of potassium cyanide followed by hydrolysis by reduction of itaconic, citraconic, and mesaconic acids by hydrolysis of ketovalerolactonecarboxylic acid by decarboxylation of 1,1,2-propane tricarboxylic acid by oxidation of /3-methylcyclo-hexanone by fusion of gamboge with alkali by hydrog. nation and condensation of sodium lactate over nickel oxide from acetoacetic ester by successive alkylation with a methyl halide and a monohaloacetic ester by hydrolysis of oi-methyl-o -oxalosuccinic ester or a-methyl-a -acetosuccinic ester by action of hot, concentrated potassium hydroxide upon methyl-succinaldehyde dioxime from the ammonium salt of a-methyl-butyric acid by oxidation with. hydrogen peroxide from /9-methyllevulinic acid by oxidation with dilute nitric acid or hypobromite from /J-methyladipic acid and from the decomposition products of glyceric acid and pyruvic acid. The method described above is a modification of that of Higginbotham and Lapworth. ... 

Pyrogallol monomethyl ether has been prepared by the methylation of pyrogallol with dimethyl sulfate or methyl iodide by the decarboxylation of 2,3-dihj droxy-4-methoxy-benzoic acid and by the methylation of pyrogallol carbonate with diazomethane and subsequent hydrolysis. The method described is taken from the improved procedure of Baker and Savage for the preparation of pyrogallol monomethyl ether from o-vanillin by oxidation with hydrogen peroxide. 

Difluoroalkenyl boranes, which are prepared in situ, are converted to difluoromethyl ketones by oxidation with hydrogen peroxide m alkaline media [720] (equation 107)... 

In an attempt to protect thiophenols during electrophilic substitution reactions on the aromatic ring, the three substituted thioethers were prepared. After acetylation of the aromatic ring (with moderate yields), the protective group was converted to the disulfide in moderate yields, 50-60%, by oxidation with hydrogen peroxide/boiling mineral acid, nitric acid, or acidic potassium permanganate. ... 

Anon., Lab. Accid. Higher Educ., item 8, Barking, HSE, 1987 During the preparation of the As-oxidc in glassware by oxidation with hydrogen peroxide (conditions unknown), an explosion occurred, possibly due to presence of impurities. 

Other valuable substrates for the domino Knoevenagel/hetero-Diels-Alder reaction are chiral oxathiolanes such as 2-778, which are easily accessible by condensation of 2-thioacetic acid and a ketone in the presence ofpTsOH, followed by oxidation with hydrogen peroxide [390]. As described by Tietze and coworkers, the Knoevenagel condensation of 2-778 with aldehydes as 2-777 can be performed in... 

Chromox [Chromium oxidation] A process for destroying organic pollutants in aqueous wastes by oxidation with hydrogen peroxide, catalyzed by Cr6+. Developed by British Nuclear Fuels in 1995, originally for use in nuclear reprocessing. 

The following procedure is based on the reaction of an aqueous solution of cobalt(II) chloride with the equivalent amount of (2-aminoethyl)carbamic acid, followed by oxidation with hydrogen peroxide and the subsequent formation of bis(ethylene-diamine)cobalt(III) ions. The bis(ethylenediamine)cobalt(lII) species are converted to the carbonato complex by reaction with lithium hydroxide and carbon dioxide. During the entire preparation a vigorous stream of carbon dioxide is bubbled through the reaction mixture. This procedure appears to be essential in order to minimize the formation of tris(ethylenediamine)cobalt(III) chloride as a by-product. However, the formation of a negligible amount of the tris salt cannot be avoided. The crude salts have a purity suitable for preparative purposes. The pure salts are obtained by recrystallization from aqueous solution. 

Asymmetric hydroboration of enamines with chiral diboranes, followed by oxidation with hydrogen peroxide, in aqueous sodium hydroxide, gives /1-amino alcohols in good yields and high ee (equation 29)153. The products of this reaction are useful in medicinal applications and as synthons for further synthetic elaboration. 

The rather unstable D-t/ reo-2,5-hexodiulosonic acid was obtained by the oxidation of D-glucose with Acetobacter melanogenum.280 2,3-Diulosonic acids are formed by oxidation of L-ascorbic acids (see Section II.5), and their formation by oxidation with hydrogen peroxide is discussed in the following chapter. 

Baeyer-Villiger oxidation.1 Aromatic aldehydes can be converted to phenols in generally high yield by oxidation with hydrogen peroxide (30%) activated by an areneseleninic acid. Polymethoxyacetophenones are also oxidized to phenols, but in lower yields. 

By using this mild and versatile methodology, symmetrical diaryl ethers have been synthesized in a one-pot, two-step procedure starting from arylboronic acids and their partial conversion to the corresponding phenols by oxidation with hydrogen peroxide and a subsequent coupling of the formed phenols with the remaining arylboronic acids upon addition of copper(II) acetate, molecular sieves and triethyl amine (Scheme 7) [22],... 

V-Hclcrocyclic aromatic compounds such as pyridines and quinolines can be converted into their /V-oxidcs by oxidation with hydrogen peroxide or peracid. Pyridine /V-oxidcs are reactive not only toward electrophilic substitution but also toward nucleophilic substitution, and, unlike pyridine, may be substituted preferentially at the 2 and 4 positions.214 Since the /V-oxidcs can readily be reduced to reproduce the parent bases, various 2- and 4-substituted pyridines and quinolines, as well as other substituted /V-helerocyclic bases, have been prepared through their N-oxides. 

Bis(phenylselanyl)methyllithiums 429 (R = H) are stable till 0 °C and were initially trapped with deuterium oxide, methyl iodide and benzophenone639. a-Substituted organolithium intermediate 429 (R = Me, w-CgH ), prepared with LiTMP in THF/HMPA at — 20 °C, reacted with alkyl bromides, ethylene oxide and benzaldehyde to give products 430 in good yields (Scheme 113)640. Bis(methylselanyl)methyllithiums 431 have been allowed to react with different electrophiles to afford products 432 (Scheme 113)640. Alkylated products have been deprotected with mercury(II) chloride or copper(II) chloride/copper(II) oxide, and by oxidation with hydrogen peroxide or benzeneseleninic anhydride644. Deprotection of selenoacetals to ketones can also be performed with sulfuric acid645. 

The reaction of MVL with trialkylboranes gave vinyl borate salts 536, which suffer alkyl migration at room temperature to give salts 537. These compounds can be transformed into vinyl ethers or methyl ketones by oxidation with hydrogen peroxide (Scheme 144)819. 

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