title: [3,3]-Sigmatropic shifts of N-allylhydrazones: quantum chemical comparison of concerted and radical cation pathways.
abstract: N-Allylhydrazones are reported to undergo an elaborate [3,3]-sigmatropic shift/N2 extrusion sequence. Both concerted and radical cation pathways for the [3,3]-sigmatropic shift of several N-allylhydrazones were investigated using B3LYP/6-31+G(d,p) calculations. It was discovered that, assuming facile formation of the N-allylhydrazone radical cation, the rearrangement takes place through a series of low barrier steps energetically preferred to the concerted alternative available to neutral N-allylhydrazones. Subsequent N2 extrusions forming corresponding homoallyl radicals were found to be extremely facile.
authors.affiliation: Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, California 95616, USA.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Siebert
authors.forename: Dean J
authors.initials: DJ
authors.lastname: Tantillo