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Published in Eli Ruckenstein, Hangquan Li, Chong Cheng, Solution and Surface Polymerization, 2019
Hongmin Zhang, Eli Ruckenstein
The diene compounds possess multiple and useful reactivities. Just as St, the dienes, especially 1,3-butadiene and isoprene, constitute some of the most important nonpolar monomers, and their polymerizations have been extensively investigated.8 Besides their polymerization capability, they can also undergo many other reactions. The addition reaction of a diene with a halogen or a halogen hydride produces halogenated compounds.9 The osmylation of a diene with osmium tetroxide generates hydroxylated products. Another most widely known reaction is the Diels–Alder reaction between conjugated diene and unlimited number of dienophiles, such as maleic anhydride, acrolein, alkyl propenoate, cyanoethene, etc.10
Basics of Crude Oil Refining
Published in Soni O. Oyekan, Catalytic Naphtha Reforming Process, 2018
Another class of unsaturated hydrocarbons that could be found in crude oil fractions and especially from downstream processing units after the crude atmospheric and vacuum distillation units are dienes and acetylenes. Hydrocarbon compounds classified as dienes are characterized by having two double bonds in their molecular structure. The predominant ones include propadiene, butadienes, and pentadienes, which could be present in appreciable concentrations in the olefin feed to the alkylation process unit. Diene compounds are sometimes removed in special catalytic process units upstream of the alkylation unit.
Chemicals from Olefin Hydrocarbons
Published in James G. Speight, Handbook of Petrochemical Processes, 2019
Dienes are aliphatic compounds having two double bonds. When the double bonds are separated by only one single bond, the compound is a conjugated diene (conjugated diolefin). Nonconjugated diolefin derivatives have the double bonds separated (isolated) by more than one single bond. This latter class is of little industrial importance. Each double bond in the compound behaves independently and reacts as if the other is not present. Examples of nonconjugated dienes are 1,4-pentadiene and 1,4-cyclo-hexadiene. Examples of conjugated dienes are 1,3-butadiene and 1,3-cyclohexadiene.
Statistical analysis of activation and reaction energies with quasi-variational coupled-cluster theory
Published in Molecular Physics, 2018
Joshua A. Black, Peter J. Knowles
Two databases were chosen to investigate solely reaction energies (ΔE): ISOMER20. A closed-shell subset of this database was constructed from the 20 original organic isomerisation reactions [20]; this now consists of reaction energies for 16 endothermic reactions. These include isomerisations of small molecules like hydrogen cyanide and isocyanic acid, and larger molecules like ketene and acetaldehyde.DARC consists of 14 exothermic Diels–Alder reactions [16,21]. These include reactions of dienes like butadiene and cyclopentadiene with ethene, ethyne, maleine and maleimide.