Wydział Chemii

V. E. Borisenko

D. S. Kuzmin

A. V. Morev

Aleksander Koll

2000

Journal of Molecular Liquids

88

259-276

10.1016/S0167-7322(00)00144-6

Naukowa

Angielski

Artykuł

The M^(0),, M⁽¹⁾ and spectral moments of the v(NH) bands of aniline derivatives as well as their complexes with various proton acceptors in solution were determined in the temperature range 285–330K. Studied compounds were: aniline; 4-metoxytetrafluoraniline; 2,3,5,6-tetrafluoraniline and 4-aminotetrafluorpyridine. The coefficients of linear Y=aT+b regression of the spectral moments M^(0),, M⁽¹⁾ and with temperature were determined for the free amino groups as well as for 1:1 complexes with various proton acceptors in CCl₄ solutions. An analysis of the influence of temperature on the spectral characteristics of monomers and their 1:1 complexes with various proton acceptors was performed. The heat formation (ΔH₁) of the 1:1 complexes with proton acceptors was determined using the dependence of the equilibrium constants on temperature.On the basis of the “rule of intensity”: the ΔH₂ for the complexes of 1:2 stoichiometry was calculated, allowing the estimation of the relation ΔH₁/ΔH_2.It was shown that ΔH₁ is larger than ΔH₂ recalculated for a single bond.Comparison of the dynamics characteristics of the N-H bonds in amino groups in complexes of different stoichiometry proves that the hydrogen bonds in 1:1 complexes is stronger than in the complexes of 1:2 stoichoimetry.

aniline derivatives, hydrogen bonding, spectral characteristics of NH stretching bands, temperature effects, enthalpy of complex formation

https://doi.org/10.1016/S0167-7322(00)00144-6

http://www.elsevier.com