title: Slow interconversion of enantiomeric conformers or atropisomers of anilide and urea derivatives of 2-substituted anilines.
abstract: N-Acylated 2-substituted anilines undergo slow Ar-N bond rotation, allowing in some cases isolation of enantiomeric or diastereoisomeric atropisomers and in others the determination of the rate of Ar-N bond rotation by NMR. 2-Iodoanilides bearing a branched N-substituent demonstrate sufficient enantiomeric stability to be resolvable, either by HPLC or by formation of diastereoisomeric lactanilide derivatives. For the first time, the rates of Ar-N rotation in 2-substituted N,N'-diarylureas have been established: they mainly fall in the region of 50-70 kJ mol(-1) with a relatively weak dependence on substituent size.
authors.affiliation: School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK.
authors.forename: Thomas
authors.initials: T
authors.lastname: Adler
authors.forename: Josep
authors.initials: J
authors.lastname: Bonjoch
authors.forename: Jonathan
authors.initials: J
authors.lastname: Clayden
authors.forename: Mercè
authors.initials: M
authors.lastname: Font-Bardía
authors.forename: Mark
authors.initials: M
authors.lastname: Pickworth
authors.forename: Xavier
authors.initials: X
authors.lastname: Solans
authors.forename: Daniel
authors.initials: D
authors.lastname: Solé
authors.forename: Lluís
authors.initials: L
authors.lastname: Vallverdú
mesh_terms: D000813:Anilides / Q000737:chemistry*; D000814:Aniline Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D008968:Molecular Conformation; D013237:Stereoisomerism; D014508:Urea / Q000031:analogs & derivatives / Q000737:chemistry*
chemical_list: D000813:Anilides; D000814:Aniline Compounds; D014508:Urea