Structural features in epoxy networks from N-diglycidyl epoxies and amines: 1. Dominant intramolecular cyclization reaction in the reactions of N, N-diglycidylaniline with aniline and substituted anilines

Abstract

The reactions of N, N-diglycidylaniline with aniline, 2,6-dimethylaniline, 2,6-dichloroaniline, 2,4,6-trichloroaniline, 3-trifluoromethylaniline and 3,5-bis(trifluoromethyl)aniline were investigated. The formation of similar amounts of the cis (equatorial/equatorial dihydroxy arrangement) and trans (axial/equatorial dihydroxy arrangement) isomers of the eight-membered 3,7-dihydroxy-perhydro-1,5-diazocine ring was the predominant intramolecular cyclization reaction. Steric effects were more important than polar effects in determining the extent of cyclization to the extent that the combined yields of cis and trans isomers was increased from ≈15% with aniline to ≈45% with 2,6-dimethylaniline. Conformational structural assignments were made on the basis of 1H and 13C nuclear magnetic resonance spectroscopy and infrared spectroscopy at high dilution.