Dissociation energy of N-H bonds in diatomic aromatic amines

The dissociation energies of N-H bonds (D, kJ/mol) were calculated by the intersecting parabolas method using the kinetic data for the following aromatic diamines: para-phenylenediamine (359.8), N,N'-dimethyl-para-phenylenediamine (348.9), N-dimethyl-N'-methyl-para-phenylenediamine (342.4), N,N'-diphenyl-para-phenylenediamine (352.8), N,N'-diphenylethylenediamine (372.7), N,N'-diheptylethylenediamine (373.3), N,N'-di-(4,4'-ethoxyphenyl)ethylenediamine (363.3), N,N'-di-(4,4'-diisopropylphenyl)-para-phenylenediamine (344.6), 4-{[dimethyl(4-phenylamino)phenoxy)silyl]oxy}-N-phenylaniline (353.4), N,N'-di-beta-naphthyl-para-phenylenediamine (354.6), N,N'-di-beta-naphthoxy-para-phenylenediamine (353.7), 1,1'-dinaphthyl-2,2'-bis-N,N'-phenyldiamine (372.9), 1,1'-dinaphthyl-2,2'-bis-N,N'-beta-naphthyldiamine (384.2), and 2,6-bis[(1E)-1-(2-phenylhydrazin-1-ylidene)ethyl]pyridine (367.9). Individual dissociation energies for the two N-H bonds were determined in N-phenyl-N'-isopropyl-para-phenylenediamine: D(PhN-H) = 352.5 and D(Me2CHN-H) = 348.7 kJ/mol.