Atropisomeric Properties of <i>N</i>-Alkyl/Aryl 5<i>H</i>-Dibenz[<i>b</i>,<i>f</i>]azepines

Abstract

The atropisomeric properties of N-alkyl and N-aryl 4-substituted 5H-dibenz[b,f ]azepines were investigated. The N-alkylation and N-arylation of 4-Cl or 4-Me substituted compounds was performed; however, none of the atropisomers produced were separated by chiral HPLC. Notably, we observed that the rotation of the four axes (ax. 1-4) in the 4-substituted 5H-dibenz[b,f ]azepine structure is so rapid that N-alkylation or N-arylation is not sufficient to freeze it at room temperature. Additionally, the X-ray crystal structures of N-aryl compounds 13b and 14a indicated that the N atom in the triphenyl amine moiety in their structures shows sp 2 -like property.