Journal of the American Chemical Society, Vol.124, No.40, 11936-11939, 2002
Viscosity-control led, product-selective rearrangement of the cyclopentane-1,3-diyl radical cation derived from an annelated housane by electron transfer: A case of Curtin-Hammett behavior
The fractional-power viscosity dependence of the product ratio [2]/[3] similar to eta(a3 a2) manifests the different free-volume requirements for the methylene (k(3) similar to eta(a3)) versus methyl (k(2) similar to eta(a2)) migrations. The syn/anti-conformational changes (k(1), k(-1)) in the radical cation 1(.+) proceed faster than the structural transformations (k(2), k(3)), which constitutes the first Curtin-Hammett case in radical-cation rearrangements.