title: The first azacyclopentenyl carbinyl radical isomerizations (ACCRI): independent use of steric and electronic (polarization) effects as gating elements.
abstract: The first examples of the azacyclopentenyl carbinyl radical isomerization are described within a series of enantiomerically enriched 2-substituted indolines, a substructure found extensively in both heterocyclic and natural product chemistry. The isomerization was identified by the varying loss of enantiomeric enrichment (ee) of imines during aryl radical cyclizations to azomethine nitrogen. Independent modification of the steric and electronic nature of the ring substituents revealed the full spectrum of sensitivity to these variables and ultimately defined the use of these effects as gating elements. An example is also given in which a 1,4-amino group transfer is effected via the isomerization mechanism. Analogies are drawn between the title isomerization and the azacyclopropyl carbinyl radical isomerization that has been studied in both chemical and biological contexts.
authors.affiliation: Department of Chemistry, Indiana University, Bloomington, Indiana 47405-7102, USA.
authors.forename: Rajesh
authors.initials: R
authors.lastname: Viswanathan
authors.forename: Daniel
authors.initials: D
authors.lastname: Mutnick
authors.forename: Jeffrey N
authors.initials: JN
authors.lastname: Johnston
mesh_terms: D001372:Aza Compounds / Q000737:chemistry*; D003517:Cyclopentanes / Q000737:chemistry*; D005609:Free Radicals / Q000737:chemistry; D007211:Indoles / Q000737:chemistry*; D007536:Isomerism
chemical_list: D001372:Aza Compounds; D003517:Cyclopentanes; D005609:Free Radicals; D007211:Indoles