Thermal reversible isomerisation of 2-ethyl-cis-penta-1,3-diene to 4-methyl-trans-hexa-1,3-diene
- 1 January 1969
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in J. Chem. Soc. A
- p. 733-735
- https://doi.org/10.1039/j19690000733
Abstract
The reversible isomerisation of 2-ethyl-cis-penta-1,3-diene to 4-methyl-trans-hexa-1,3-diene is an example of the now well-authenticated 1,5-hydrogen migration reaction which occurs in a number of diene systems. The reaction is almost certainly unimolecular and the first-order rate constants, obtained in the temperature range 190–250° fit the Arrhenius equations, k1= 1010·77 exp (–31,640/RT) sec.–1; k–1= 1011·03 exp (-34,530/RT) sec.–1. Equilibrium constants have been determined by direct analysis in the range 230–340° and hence enthalpy and entropy differences between the isomers have been evaluated. The A factors of the isomerisations are discussed and compared with estimated values.Keywords
This publication has 0 references indexed in Scilit: