Computational Thermochemistry of Six Ureas, Imidazolidin-2-one, N,N '-Trimethyleneurea, Benzimidazolinone, Parabanic Acid, Barbital (5,5 '-Diethylbarbituric Acid), and 3,4,4 '-Trichlorocarbanilide, with an Extension to Related Compounds

A computational study of the structural and thermochemical properties of N-phenyl (open) and N-alkyl (cyclic) ureas, through the use of M05-2X and B3LYP density functional theory calculations has been carried out. The consistency of the literature experimental results has been confirmed, and using m...

ver descrição completa

Detalhes bibliográficos
Autor principal: Juan Z Davalos (author)
Outros Autores: Maria das Dores C R Ribeiro da Silva (author), Manuel A V R Ribeiro da Silva (author), Vera L S Freitas (author), Pilar Jimenez (author), Maria Victoria Roux (author), Pilar Cabildo (author), Rosa M Claramunt (author), Jose Elguero (author)
Formato: article
Idioma:eng
Publicado em: 2010
Assuntos:
Texto completo:https://repositorio-aberto.up.pt/handle/10216/94750
País:Portugal
Oai:oai:repositorio-aberto.up.pt:10216/94750
Descrição
Resumo:A computational study of the structural and thermochemical properties of N-phenyl (open) and N-alkyl (cyclic) ureas, through the use of M05-2X and B3LYP density functional theory calculations has been carried out. The consistency of the literature experimental results has been confirmed, and using mainly isodesmic reactions, the unknown Delta fH(0)(g) of the other urea derivatives were estimated. The experimental results together with the theoretical information have permitted the study of the effect of phenyl, p- and m-chlorophenyl, alkyl, and carbonyl substitutions on the thermodynamical stability of urea and its cyclic derivatives. The peculiar behavior of the N-tert-butyl substituent in cyclic ureas has been related to geometric deformations.