Highly diastereoselective radical cyclizations on soluble ring opening metathesis supports.
This study represents the first examples of stereoselective radical cyclizations on soluble supports. A stereocontrol element consisting of a polymer-imbedded (+)-isosorbide chiral auxiliary was used in each monomer subunit. A survey of various Lewis acids was also examined. The best results gave very high distereoselectivites of >100:1 in a hepa-1,3-dienenyl radical cyclization using zinc chloride as a Lewis acid. [reaction: see text]
Enholm
E J
EJ
Department of Chemistry, University of Florida, Gainesville, FL 32611, USA. enholm@chem.ufl.edu
Cottone
J S
JS