title: N to C aryl migration in lithiated carbamates: alpha-arylation of benzylic alcohols.
abstract: We report a new mode of reactivity displayed by lithiated O-benzyl carbamates carrying an N-aryl substituent: upon lithiation, the N-aryl group is transferred cleanly from N to C. An arylation of the carbamate results, providing a route to alpha,alpha-arylated secondary or tertiary alcohols. We also report density functional theory calculations supporting the proposal that arylation proceeds through a dearomatizing attack on the aromatic ring, a significantly lower energy pathway than the 1,2-acyl transfer observed with related N-alkyl carbamates.
authors.affiliation: School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK. clayden@man.ac.uk
authors.forename: Jonathan
authors.initials: J
authors.lastname: Clayden
authors.forename: William
authors.initials: W
authors.lastname: Farnaby
authors.forename: Damian M
authors.initials: DM
authors.lastname: Grainger
authors.forename: Ulrich
authors.initials: U
authors.lastname: Hennecke
authors.forename: Michele
authors.initials: M
authors.lastname: Mancinelli
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Tetlow
authors.forename: Ian H
authors.initials: IH
authors.lastname: Hillier
authors.forename: Mark A
authors.initials: MA
authors.lastname: Vincent