Pyrolysis products, possibly derived

Very few reactions of the 1,4,2,5-oxadiazine ring have been reported. Flash-vacuum pyrolysis of 3,6-diaryl derivatives gives aromatic nitriles as the main products, together with products possibly derived from an aroylnitrene,20 and hydrogenolysis gives the corresponding amides. 

The involvement of tobacco smoke carcinogens in the aetiology of lung cancer is conclusively established, but the role of specific chemical carcinogens as inducers of colorectal cancer is much less clear. Mutagenic pyrolysis products derived from cooked food have come under suspicion as possible... 

Unlike melinonine A, pyrolysis of melinonine B chloride does not give a good yield of the corresponding tertiary base. The only crystalline product from the reaction is a base, mp 196.5°-198.5° designated Tx, obtained in low yield, which is not converted into the parent alkaloid by methylation it appears to be an Aa-methyl derivative of the desired nor base formed by a transmethylation reaction. Methylation and chromatography of the amorphous pyrolysis product show that some normelinonine B is present, but it was not possible to isolate it. 

While it is possible to recover the bicyclic naphthalene from pyrolysis products of coal and petroleum-derived raw materials, the tricyclic anthracene can be isolated only from high-temperature coal tar, since anthracene is present only in small amounts in other pyrolysis products and in the residues of catalytic hydrocarbon conversion. 

A very rigorous procedure (Fairburn, 1988), developed over the years, is implemented for each run. This methodology and the above described system have been proven very reliable and successful in providing the best possible qualitative and quantitative information on the product distribution derived from pyrolysis of various materials under carefully controlled temperatures and reaction times. Wires have been utilized in the experimental work having Curie Point temperatures from 300 to 1000°C and experiments performed with various feedstocks with carefully controlled reaction times between 50 and 2000 milliseconds. 

In the case of the cyclohexane derivative 7 however, that bears an equatorial acetate group, two axial cis-/3-hydrogens are available, and elimination in both directions is possible. The pyrolysis of 7 yields the two elimination products 8 and 6. Formation of product 8 is strongly favored, because the new double bond is in conjugation to the ester carbonyl group. ... 

It is possible to produce some liquid hydrocarbons from most coals during conversion (pyrolysis and hydrogenation/ catalytic and via solvent refining)/ but the yield and hydrogen consumption required to achieve this yield can vary widely from coal to coal. The weight of data in the literature indicate that the liquid hydrocarbons are derived from the so-called reactive maceralS/ i.e. the vitrinites and exinites present (7 8 1 9). Thusf for coals of the same rank the yield of liquids during conversion would be expected to vary with the vitrinite plus exinite contents. This leads to the general question of effect of rank on the response of a vitrinite and on the yield of liquid products and/ in the context of Australian bituminous coals, where semi-fusinite is usually abundant/ of the role of this maceral in conversion. 

Several cases of spontaneous ignition after exposure to air of fine coke particles removed from filter strainers on a petroleum refinery furfural extraction unit have been noted. This has been associated with the use of sodium hydrogen carbonate (bicarbonate) injected into the plant for pH control, which produced a pH of 10.5 locally. This would tend to resinify the aldehyde, but there is also the possibility of a Cannizzaro reaction causing conversion of the aldehyde to furfuryl alcohol and furoic acid. The latter, together with other acidic products of autoxidation of the aldehyde, would tend to resinily the furfuryl alcohol. Pyrolysis GLC showed the presence of a significant proportion of furfuryl alcohol-derived resins in the coke. The latter is now discarded into drums of water, immediately after discharge from the strainers, to prevent further incidents. 

Dr. Friedel. No. Products of the pyrolysis of coal under high temperature carbonization conditions surely must arise from degradation. The quantitative prediction of C7 alkane isomers from coal may possibly indicate a relationship in compositions of coal and petroleum. The hydrocarbons from each perhaps should be similar since both are supposedly derived from organic plants ... 

A large number of HNCC of osmium have been produced from the vacuum pyrolysis of Os3(CO)i2 and some of its derivatives (Scheme 1). The reaction of Os3(CO)i2 has been shown to be extremely sensitive to temperature, time, and moisture, giving a series of products whose nuclearities range from 5 to 11 and possibly higher 41, 54, 80, 134). By optimizing the conditions, yields up to 80% of Os6(CO)ig have been obtained 41). High specificity has also been observed in the vacuum pyrolysis of Os3(CO)ii(C5H5N), from which [OsioC(CO)24j] has been obtained in 65% yield 80). 

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