933-98-2Relevant academic research and scientific papers
Evolution of products in the combustion of scrap tires in a horizontal, laboratory scale reactor
Fullana,Font,Conesa,Blasco
, p. 2092 - 2099 (2007/10/03)
A horizontal laboratory reactor was used to study the evolution of byproducts from the combustion of scrap tires at five nominal temperatures (ranging from 650 to 1050 °C) and different oxygen:sample ratios A model was used to calculate the bulk air ratio (λ), and the oxygen consumption was discussed considering this ratio λ. More than 100 volatile and semivolatile compounds were identified and quantified by gas chromatography mass spectrometry, plotting their yields vs the bulk air ratio and temperature. Five different behaviors considering the bulk air ratio and the temperature were identified.
Dependence of the Lewis Acid-Induced Reaction of β-Stannyl Ketones upon Substitution Pattern: Cyclopropanation versus 1,2-Alkyl Migration
Fujiwara, Jun,Sato, Tadashi
, p. 1258 - 1264 (2007/10/02)
3-Stannylcyclohexanones fully substituted at 2 and 3 positions underwent a 1,2-aklyl migration, along with the cyclopropanation.The balance of the reactions depended upon the steric environment and migratory aptitude of the alkyl groups.
78. Ueber den Anteil sigmatroper 1,5-Wanderung von Kohlenwasserstoffgruppen bei der thermolytischen Skelettisomerisierung 5,5-disubstituierter 1,3-Cyclohexadiene
Schiess, Peter,Dinkel, Rolf
, p. 801 - 812 (2007/10/02)
The uncatalyzed skeletal isomerization of 5,5-disubstituted 1,3-cyclohexadienes was investigated with the aim to establish the extent to which sigmatropic 1,5-shifts of hydrocarbon groups are participating in these reactions.Gas phase pyrolysis of 5,5-diethyl-1,3-cyclohexadiene (7) at 460 deg C followed by chloranil aromatization yields only 4percent of 1,3-diethylbenzene resulting from 7 through a 1,5-ethyl migration in the primary reaction step 2,3-Dimethylethylbenzene (56percent) and 1,4-diethylbentene (4percent) are obtained as other C10-compounds.This shows that isomerization proceeds mainly through a sequence of electrocyclic and 1,7-shift reactions.Ethylbenzene (24percent) and other aromatic C8- and C9-hydrocarbons are formed to a considerable extent, indicating that C,C-bond cleavage is a major competing process and that the 1,3-diethylbenzene found is the result of a radical recombination reaction and not of a concerted sigmatropic shift of the ethyl group. 5-Methyl-5-phenyl-1,3-cyclohexadiene (12) yields 3-methylbiphenyl (14) and biphenyl upon thermolysis and aromatization.Through 13C-substitution of the methyl group in 12 it is shown that in solution at 300 deg skeletal isomerization proceeds through electrocyclic and 1,7-H-shift reactions exclusively.In the gas phase at 500 deg 4percent of the isomerization product is formed by a 1,5-shift of a substituent, presumably of the methyl group, through a dissociative mechanism.Thermolysis of 5,5-diphenyl-1,3-cyclohexadiene (22) at 560 deg in the gas phase leads to 1,1-diphenyl-1,3,5-hexatriene (23) and 1-vinyl-4-phenyl-1,2 dihydronaphthalene (24) through electrocyclic reaction steps.In addition a small amount of m-terphenyl is obtained at high conversion of 22.This indicates that sigmatropic 1,5-phenyl migration can participate in product formation only at high temperature and in the absence of other irreversible pathways to stable products.
Process for the preparation of substituted vinylbenzyl chloride
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, (2008/06/13)
An improved continous single step vapor phase process for the preparation of substituted vinylbenzyl chloride from substituted ethyltoluene is disclosed. In this process a substituted ethyltoluene is reacted with a halogen gas in the vapor phase, at elevated temperatures via a continuous feed process. Furthermore, this process achieves halogenation followed by dehydrohalogenation in a single pass through the reactor. There is also obtained a very high total selectivity to vinylbenzyl chloride and its precursors via this continuous process.
