Reaction Pathways of Methyl Radical and Ethylamine

Abstract

The mechanisms for the reaction of methyl radical with ethylamine were determined by the density functional theory using the atomic structures of the reactants, transition states and products optimized at the B3LYP/6-311++G(3df,2p) level of theory. Seven transition states were identified for the production of CH₃CHNH₂ + CH₄ (TS1), CH₃CH₂NH + CH₄ (TS2), CH₂CH₂NH₂ + CH₄ (TS3), CH₃CH₂NHCH₃ + H (TS4), CH₃CH₂ + CH₃NH₂ (TS5), C₂H₆ + CH₂NH₂ (TS6) and C₃H₈ + NH₂ (TS7) with the corresponding barriers, 9.34, 9.90, 13.46, 27.70, 39.12, 45.82 and 69.34 kcal/mol. Thermodynamics analysis and potential energy surface show that H-abstraction pathways took place easier than NH₂-, CH₃–abstractions, H-substitution of the NH₂ group and CH₃-substitution in ethylamine. The H-abstraction in methylene group of ethylamine was the most favourable on the PES of this reaction system.

Keywords

Methyl, Ethylamine, B3LYP, transition states

References

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