Hydrogen peroxide, pyrolysis

The process starts from tricyclohexylidene triperoxide which is obtained by oxidation of cyclohexanone with hydrogen peroxide. Pyrolysis leads to a mixture of 1,16-hexadecanolide and cyclopentadecane. The latter is oxidized by oxygen under boric acid catalysis to cyclopentadecanol which is subsequently oxidized to cyclopentadecanone [124,124a]. 

Isoprene (2-methyl-1,3-butadiene) can be telomerized in diethylamine with / -butyUithium as the catalyst to a mixture of A/,N-diethylneryl- and geranylamines. Oxidation of the amines with hydrogen peroxide gives the amine oxides, which, by the Meisenheimer rearrangement and subsequent pyrolysis, produce linalool in an overall yield of about 70% (127—129). 

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. ... 

Disulfides can be prepared by treatment of alkyl halides with disulfide ions and also indirectly by the reaction of Bunte salts (see 10-41) with acid solutions of iodide, thiocyanate ion, or thiourea, or by pyrolysis or treatment with hydrogen peroxide. Alkyl halides also give disulfides when refluxed with sulfur and NaOH, and with piperidinium tetrathiotungstate or piperidinium tetrathiomolybdate. ... 

Intensification can be achieved using this approach of combination of cavitation and advanced oxidation process such as use of hydrogen peroxide, ozone and photocatalytic oxidation, only for chemical synthesis applications where free radical attack is the governing mechanism. For reactions governed by pyrolysis type mechanism, use of process intensifying parameters which result in overall increase in the cavitational intensity such as solid particles, sparging of gases etc. is recommended. 

T0387 Hydrocarbon Technologies, Inc., Recovered Oil Pyrolysis and Extraction (ROPE) T0388 Hydrogen Peroxide In Situ Bioremediation—General... 

V (at oxygen consumption over 90%) indicates that Reactor III gave the highest selectivity (ca. 60% ) as to hydrogen peroxide formation, and the lowest yield of by-products from pyrolysis and combustion. Reactor... 

TCBTs are relatively persistent and non-flammable (and therefore useful in hydraulic oils). Pyrolysis in a closed system for two days in the presence of hydrogen peroxide at 300 °C produced as main components chlorinated benzo-phenones, fluorenes, fluorenones, xanthenes, and xanthones. Polychlorodiben-zofurans (PCDF) and polychlorodibenzo-p-dioxins (PCDD) were formed in much lower concentrations than from PCB product Pyralene T1 under identical conditions [84]. In pyrolysis at 450-700 °C with excess oxygen TCBTs produce more PCDFs and PCDDs. In parallel with the behavior of PCBs, PCDFs are formed in significantly higher amounts than PCDDs from PCBTs [86],... 

Sodium thiosulfate reacts with alkyl halides to form salts of the type RSSOjNa (Bunte salts). Alkyl disulfides may be obtained from these salts by pyrolysis or reaction with iodine or hydrogen peroxide. The yields range from 47% to 6S>%. Cyano and carboxyl groups do not interfere. Benzoylation of sodium thiosulfate produces benzoyl disulfide in 58% yield. ... 

This ester oxidizes very easily [95], reaction being perceptible even below 140 °C. Above about 300 °C, pyrolysis to propene and acetic acid also takes place. It too, gives cool flames [47]. Fish and Waris [95] detected only acetone, organic peroxides and peroxyacids in the products. Between 280 and 360 °C, Hoare and Kamil [97] found a wider range of products including hydrogen peroxide, formaldehyde, methanol, isopropanol, acetic acid and at 320 °C and below, acetaldehyde. Propene and acetone were found at 360 °C but organic peroxides and peroxyacids were always absent. 

In an alternative procedure the decomposition is effected by the use of concentrated sulphuric acid and potassium sulphate, followed by the addition of 30% hydrogen peroxide. The solution is adjusted to 6 N with respect to hydrochloric acid and antimony is extracted with diisopropyl ether. Colour is developed by the addition to the ether phase of 0.02% Rhodamine B in IN hydrochloric acid . Compounds containing trivalent antimony which are unstable in oxygen or moist air may be stabilized by exposure to sulphur for 8-48 h in vacuo and the resulting compounds are examined by pyrolysis . 

Recent work has cast doubt on the previous conclusions that ring E of strychnine is a five-membered ring. The a-ketoamide of dihydrostrych-ninone (Ci9His08N2) has been oxidized by barium hydroxide-hydrogen peroxide to carbon dioxide and an amino acid, cuninecarboxylic acid (C18H20O3N2) (232). The carboxyl of this j3-amino acid (on formula XV for strychnine) should be lost by pyrolysis, but on the contrary lactamiza-tion occurred. This unexpected lactamization is explained most satisfactorily by the assumption of a piperidine nucleus for ring E (LXXXIX). 

Oxidation of bicyclic borane (2) with hydrogen peroxide in the presence of base leads to 1,5,9-nonanetriol (15) (Scheme 3) . It should be stressed that the combination of the three consequent reactions (hydroboration-pyrolysis-deboration) results in a unique approach for the transformation of monoalkenes to organic compounds containing three functional groups. Thus, a mixture of nonenes can be converted to 1,5,9-nonanetriol (15). 

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