Fragmentation of ring-fused cyclopropylcarbinyl radicals: Effect of ring size

CHED 302

Eric J. Kantorowski, ekantoro@calpoly.edu, Caleb Hunt, and Daniel Le. Department of Chemistry and Biochemistry, California Polytechnic State University, 1 Grand Ave, San Luis Obispo, CA 93407
Cyclopropylcarbinyl radical, when angularly fused onto an existing ring, can fragment across the shared bond to provide the corresponding ring-expanded homoallylic radical. Alternatively, fragmentation of the exo bond leads to a non-expanded homoallylic radical. The direction of fragmentation is dependent on the size of the attached ring and is subject to kinetic and thermodynamic control. Thermokinetic data for the prototypical system, 1-methylbicyclo[n.1.0]alkyl-1-yl radical (n = 4, 5, 6, etc.), will be presented.