Conformational dynamics of substituted N-acetyl-N-phenylbenzylamines.: <SUP>1</SUP>H-DNMR and AM1-MO study

Simple item page
dc.contributor.authorWeiss-López, BE
dc.contributor.authorJullian, C
dc.contributor.authorSaitz, C
dc.contributor.authorPessoa-Mahana, H
dc.contributor.authorValderrama, J
dc.contributor.authorAraya-Maturana, R
dc.date.accessioned2025-01-21T01:30:44Z
dc.date.available2025-01-21T01:30:44Z
dc.date.issued2001
dc.description.abstractActivation parameters for the rotation around the methylene-nitrogen single bond found in a series of four 2,2'-disubstituted N-acetyl-N-phenylbenzylamines, dissolved in DMSO-d(6), were measured employing the temperature dependence of the H-1-NMR spectrum lineshape between 340 and 400 K. The results are (I) 2 - [N-acetyl -N- (2-acetamidophenyl) aminomethyl] phenyl acetate DeltaG(not equal) =79.9 +/-2.0 kJ/mol (370K), DeltaH(not equal) =96.2 +/-6.0 kJ/mol and DeltaS(not equal) =+45 +/- 20 J/Kmol; (II) 2 [N - acetyl - N - (2-acetyioxybenzyl)amino]benzylacetate DeltaG(not equal) =82.0 +/-2.0 kJ/mol (370K), DeltaH(not equal) =79.1 +/-6.0 kcal/mol and DeltaS(not equal) =8 +/- 20 J/Kmol; (III) 2 - [N - Acetyl - N - (2-nitrobenzyl)amino]benzylacetate DeltaG(not equal) =80.8 +/-2.0 kJ/mol (380K), DeltaH(not equal) =60.7 +/-6.0 kcal/mol and DeltaS(not equal) =53 +/- 20 J/Kmol; (IV) 2-[N-Acetyl-N-(2-acetyloxybenzyl)amino]phenylacetate DeltaG(not equal) =77.0 +/-2.0 kJ/mol (370K), DeltaH(not equal) =65.3 +/-6.0 kJ/mol and DeltaS(not equal) =-32 +/- 20 J/Kmol. Substitution at positions 2 and 2' with bulky groups appears to be essential to freeze the gauche structure at room temperature and consequently, the main contribution to the barrier arises from the steric hindrance between these two groups. Structure I shows an anomalous behavior, possibly due to the formation of a hydrogen bond between the NH at position 2' and the solvent. This interaction increases DeltaH pi and freezes the rotation around the aryl-nitrogen bond, increasing DeltaS(not equal).
dc.fuente.origenWOS
dc.identifier.issn0366-1644
dc.identifier.urihttps://repositorio.uc.cl/handle/11534/96876
dc.identifier.wosidWOS:000172210200005
dc.issue.numero3
dc.language.isoen
dc.pagina.final269
dc.pagina.inicio261
dc.revistaBoletin de la sociedad chilena de quimica
dc.rightsacceso restringido
dc.subjectconformational dynamics
dc.subjectH-1-NMR
dc.subjectN-acetyPhenylbenzylamines
dc.subjectAM1-MO
dc.subject.ods03 Good Health and Well-being
dc.subject.odspa03 Salud y bienestar
dc.titleConformational dynamics of substituted N-acetyl-N-phenylbenzylamines.: <SUP>1</SUP>H-DNMR and AM1-MO study
dc.typeartículo
dc.volumen46
sipa.indexWOS
sipa.trazabilidadWOS;2025-01-12
Files
Collections
Artículos de revistas