title: N,N'-diarylureas: a new family of atropisomers exhibiting highly diastereoselective reactivity.
abstract: 2,6-disubstituted N-aryl ureas rotate slowly about their Ar-N bonds and can exist as separable atropisomers. They also react remarkably diastereoselectively, with the urea axis controlling new stereogenic centers with high fidelity in a variety of nucleophilic and electrophilic addition reactions. The sense of diastereoselectivity in lateral lithiation-electrophilic quench reactions is electrophile-dependent and appears to be the result of stereospecific reaction with one of two interconvertible diastereoisomeric organolithiums.
authors.affiliation: School of Chemistry, University of Manchester, Manchester, UK. clayden@man.ac.uk
authors.forename: Jonathan
authors.initials: J
authors.lastname: Clayden
authors.forename: Hazel
authors.initials: H
authors.lastname: Turner
authors.forename: Madeleine
authors.initials: M
authors.lastname: Helliwell
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Moir