Kinetics and regioselectivity of ring opening of 1-bicyclo[3.1.0]hexanylmethyl radical.
Rate constants for the rearrangement of 1-bicyclo[3.1.0]hexanylmethyl radical (2) to 3-methylenecyclohexenyl radical (3) and 2-methylenecyclopentyl-1-methyl radical (1) were measured using the PTOC-thiol competition method. The ring-expansion pathway is described by the rate equation, log(k/s-1) = (12.5 +/- 0.1) - (4.9 +/- 0.1)/theta; the non-expansion pathway is described by log(k/s-1) = (11.9 +/- 0.6) - (6.9 +/- 0.8)/theta. Employing the slower trapping agent, tri-n-butylstannane, favors methylenecyclohexane over 2-methyl-methylenecyclopentane by more than 120:1 at ambient or lower temperatures.
Kantorowski
Eric J
EJ
Department of Chemistry and Biochemistry, California Polytechnic State University, San Luis Obispo, California 93407, USA. ekantoro@calpoly.edu
Le
Daniel D
DD
Hunt
Caleb J
CJ
Barry-Holson
Keegan Q
KQ
Lee
Jessica P
JP
Ross
Lauren N
LN