Dimethyl carbonate, pyrolysis

Fabbri, D., Baravelli, V., Chiavari, G., and F rati, S. Profiling fatty acids in vegetable oils by reactive pyrolysis-gas chromatography with dimethyl carbonate and titanium silicate. Journal of Chromatography A, 1083, 52-57. 2005. 

Fig. 4.24 Heat of immersion of a carbon (prepared by pyrolysis of Saran Polymer A) in different liquids at 300 K. The liquids for points 1-6 were (I) methanol (2) benzene (3) n-hexane (4) 3-methyl benzene (5) 2,2-dimethyl butane (6) 2,2,4-trimethyl pentane. The abscissae represent the molar volumes of the liquids. (Redrawn from the original diagram of Barton, Beswick and Harrison. " )...

On thermolysis of bis(trimethylsilyl) malonate 337 at 160°C in the presence of P4O10 carbon suboxide 339 is formed in 54% yield, via 338 two equivalents of tri-mefhylsilanol 4 are also formed and react in situ with P4O10 to give polyphosphoric acid trimethylsilylester (PPSE) 195 [118] (Scheme 4.44). Pyrolysis of trimethylsilyl 2,2-dimefhylmalonate at 700°C gives dimethyl ketene and HMDSO 7 [118a]. 

A typical determination is that of Lossing and Tickner for the methyl radical. Methyl radicals were produced by the pyrolysis of mercury dimethyl diluted by helium, and the mass spectrum showed that only CH3, mercury, ethane and a trace of methane were formed. Sensitivity calibrations were obtained in the usual way for the stable substances, and then the net peak at mass 15, after subtraction of the contributions from mercury dimethyl, ethane and methane, was determined. At high temperatures of pyrolysis, where the methyl radicals were most abundant, the sensitivity for the mass 15 peak of the methyl radical could then be calculated on the basis of 100 % carbon balance. As discussed earlier, wall reactions may lead to appreciable disappearance of the radical under observation, and such effects must be taken into account when calculating the sensitivity of the apparatus. Corrections of these kinds were applied to the experiments described above when Ingold and Lossing discovered that part of the methane observed was produced by reaction in the ionization chamber. The smallest relative concentration of radicals which can be determined accurately i.e. where several species give rise to the... 

Dimethylbicyclo[4.1.1]octa-2,4-diene (la) underwent rearrangement on direct photolysis or pyrolysis to yield 8,8-dimethylbicyclo[5.1.0]octa-2,4-diene (2a), a homolog of 7,7-dimethyl-norcaradiene (see Section 4.4.1.). This product, resulting from a 1,5-carbon shift, was the only isomer detected on irradiation through Pyrex or when the pyrolysis was conducted at 225 °C. Pyrolysis at 250°C gave a mixture of substituted cyclohepta-1,3- and -1,4-dienes 3 and 4. ... 

Many other catalytic fluidized-bed processes have been tested at various scales. These include catalytic low-temperature oxidation, catalytic gasification and pyrolysis of biomass and waste plastic, production of carbon nanotubes, dry reforming of methane, hydrogenation and dehydrogenation of hydrocarbons, methanol-to-gasoline (MTC) process, synthesis of dimethyl ether (DME), and selective catalytic reduction of nitrogen... 

An ice-cooled suspension of anhydrous K-carbonate in 2,2-dimethyl-4-pentenal said, with NHg, the flask stoppered loosely, left 2 days at room temp., the lower aq. layer removed, and the organic layer distilled through a column with collection of the product at 102°/0.5 mm-95 /0.07 mm 2,2-dimethyl-N,N -bis-(2,2-dimethyl-4-pentenylidene)-4-pentene-l,1-diamine. Y 76%. F. e. and pyrolysis of the products s. R. H. Hasek, E. U. Elam, and J. G. Martin, J. Org. Ghem. 26, 1822 (1961). 

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