Ab initio modeling of reactions of acrylamide with aliphatic di-, tri-, tetra- and pentaamines
Abstract
Ab initio modeling of reactions of acrylamide with aliphatic di-, tri-, tetra- and pentaamines
Incoming article date: 05.03.2014The paper studies the possibility of interaction of acrylamide with aliphatic di-, tri-, tetra- and pentaamines using quantum chemical ab initio modeling. The interest to the preparation of these compounds can only increase since they may serve as feedstock for the production of other useful materials which may find adequate application. The choice of reaction conditions depends on the thermodynamic principles of the process, and for that reason, the paper determines thermodynamic parameters and the logarithms of the equilibrium constants of acrylamide reaction with aliphatic amines in ratio of 1:1 and 2:1 in the gas phase by quantum-chemical method based on density functional theory using a hybrid exchange-correlation of B3LYP functions in the basis of 3 -21G* within 273 ÷ 450 K temperature range and pressure of 0.1 MPa. These calculations served as a base for defining the conditions that must be followed when developing the technology for these compounds, and it was shown that the reaction of their synthesis with high probability of acrylamide - amine reactants ratio of 2:1 should be conducted under relatively mild conditions. Theoretical calculations comply with the experiment, because the interaction of acrylamide with amines at various ratios of reagents and temperatures within 325 ÷ 330 K leads predominantly to the transformation at acrylamide-amine 2:1 reagent ratio, as evidenced by the number of reactive reagents, and frequency analysis of FT-IR, NMR 1H and 13C spectra. Thus, the possibilities of mathematical modeling allow determining the highest probability of spontaneity for a particular reaction, using the method of computer simulation by changing the process temperature (within the model) without performing any technological experiments.
Keywords: Acrylamide, aliphatic amines, ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepenta-amine, thermodynamic parameters, Gibbs free energy, isobaric-isothermal potential, equilibrium constant.