Thermal disrotatory electrocyclic isomerization of cis-bicyclo[4.2.0]oct-7-ene to cis,cis-1,3-cyclooctadiene.
[reaction: see text] The ratio of observed rate constants, k/k', for thermal isomerizations of cis-bicyclo[4.2.0]oct-7-ene and its 2,2,5,5-d(4) analogue to cis,cis-1,3-cyclooctadienes at 250 degrees C is 1.17, indicative of a secondary, not a primary, deuterium kinetic isotope effect. The reaction does not occur through a [1,5] hydrogen shift from the transient cis,trans-1,3-cyclooctadiene intermediate to form the observed cis,cis-diene product.
Baldwin
John E
JE
Department of Chemistry, Syracuse University, Syracuse, New York 13244, USA. jbaldwin@syr.edu
Gallagher
Sarah S
SS
Leber
Phyllis A
PA
Raghavan
Anuradha
A