Addition of Group VIa atoms to tetramethylethylene. Addition reaction with a negative activation energy

Abstract

The reactions of ground-state (3P2,i,o) atoms of the group Via elements with olefins have received considerable attention in recent years.1-7 Atomic oxygen yields epoxides, the isomeric carbonyl compounds, and various fragmentation products. Sulfur, selenium, and tellurium give only the cyclic adduct which, with the latter two elements, has only transient existence.

Variable Activation Energy Principle to Model Oil Shale Pyrolysis Kinetics

“…This concept was applied to oil shale kinetic study for the first time. The principle of negative activation energy has been reported and discussed by several investigators before [21][22][23][24][25][26]. It is an unrecognized fact that some chemical reactions proceed more slowly at higher reaction temperatures and therefore effectively comply with negative activation energy.…”

Laser Photolysis and Thermolysis of Organic Selenides and Tellurides for Chemical Gas-phase Deposition of Nanostructured Materials

“…Thermolysis and photolysis of ditellurides yielding elemental tellurium and telluride [ 16 , 17 , 18 ] and that of tellurides leading to feasible formation of elemental tellurium has less synthetic application. However, pyrolytic extrusion of Te from tellurides makes possible synthesis of carbocyclic systems [ 19 ] and cyclobutenes [ 20 ] and coupling of allylic halides [ 21 ], and photolytic fragmentation of dimethyl telluride [ 22 ] enables gas-phase generation of Te atoms that add to alkenes [ 23 ].…”