Experimental and theoretical study of the methoxy group conformational effect on 13C chemical shifts in ortho‐substituted anisoles

Aromatic 13C chemical shifts are reported for a number of ortho‐substituted anisoles. Quantitative determination of the substituent chemical shift (SCS) effects of the methoxy group with a fixed coplanar conformation on aryl carbon nuclei was achieved using experimental and theoretical methods. The...

Descripción completa

Detalles Bibliográficos
Autores principales: Biekofsky, R.R., Pomilio, A.B., Econteras, R.H., de Kowalewski, D.G., Facelli, J.C.
Formato: JOUR
Materias:
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_07491581_v27_n2_p158_Biekofsky
Aporte de:
id todo:paper_07491581_v27_n2_p158_Biekofsky
record_format dspace
spelling todo:paper_07491581_v27_n2_p158_Biekofsky2023-10-03T15:39:19Z Experimental and theoretical study of the methoxy group conformational effect on 13C chemical shifts in ortho‐substituted anisoles Biekofsky, R.R. Pomilio, A.B. Econteras, R.H. de Kowalewski, D.G. Facelli, J.C. 13C NMR Methoxy group conformational effect ortho‐Substituted anisoles Substituent chemical shifts Aromatic 13C chemical shifts are reported for a number of ortho‐substituted anisoles. Quantitative determination of the substituent chemical shift (SCS) effects of the methoxy group with a fixed coplanar conformation on aryl carbon nuclei was achieved using experimental and theoretical methods. The experimental values were compared with those calculated through the use of the additivity, and a systematic departure from additivity was found for carbon nuclei in ortho positions. Ortho‐SCSs were found to be non‐equivalent, and the ortho effect on the carbon cis to the fixed methoxy moiety was more shielding than in anisole. The IGLO (Individual Gauge for Localized Orbitals) method was used to calculate the SCSs. Experimental and theoretical trends obtained for the influence of the side‐chain conformations on chemical shifts are in very good agreement with each other, and with recent results obtained by solid‐state NMR. Copyright © 1989 John Wiley & Sons, Ltd. Fil:Biekofsky, R.R. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Pomilio, A.B. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Facelli, J.C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_07491581_v27_n2_p158_Biekofsky
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic 13C NMR
Methoxy group conformational effect
ortho‐Substituted anisoles
Substituent chemical shifts
spellingShingle 13C NMR
Methoxy group conformational effect
ortho‐Substituted anisoles
Substituent chemical shifts
Biekofsky, R.R.
Pomilio, A.B.
Econteras, R.H.
de Kowalewski, D.G.
Facelli, J.C.
Experimental and theoretical study of the methoxy group conformational effect on 13C chemical shifts in ortho‐substituted anisoles
topic_facet 13C NMR
Methoxy group conformational effect
ortho‐Substituted anisoles
Substituent chemical shifts
description Aromatic 13C chemical shifts are reported for a number of ortho‐substituted anisoles. Quantitative determination of the substituent chemical shift (SCS) effects of the methoxy group with a fixed coplanar conformation on aryl carbon nuclei was achieved using experimental and theoretical methods. The experimental values were compared with those calculated through the use of the additivity, and a systematic departure from additivity was found for carbon nuclei in ortho positions. Ortho‐SCSs were found to be non‐equivalent, and the ortho effect on the carbon cis to the fixed methoxy moiety was more shielding than in anisole. The IGLO (Individual Gauge for Localized Orbitals) method was used to calculate the SCSs. Experimental and theoretical trends obtained for the influence of the side‐chain conformations on chemical shifts are in very good agreement with each other, and with recent results obtained by solid‐state NMR. Copyright © 1989 John Wiley & Sons, Ltd.
format JOUR
author Biekofsky, R.R.
Pomilio, A.B.
Econteras, R.H.
de Kowalewski, D.G.
Facelli, J.C.
author_facet Biekofsky, R.R.
Pomilio, A.B.
Econteras, R.H.
de Kowalewski, D.G.
Facelli, J.C.
author_sort Biekofsky, R.R.
title Experimental and theoretical study of the methoxy group conformational effect on 13C chemical shifts in ortho‐substituted anisoles
title_short Experimental and theoretical study of the methoxy group conformational effect on 13C chemical shifts in ortho‐substituted anisoles
title_full Experimental and theoretical study of the methoxy group conformational effect on 13C chemical shifts in ortho‐substituted anisoles
title_fullStr Experimental and theoretical study of the methoxy group conformational effect on 13C chemical shifts in ortho‐substituted anisoles
title_full_unstemmed Experimental and theoretical study of the methoxy group conformational effect on 13C chemical shifts in ortho‐substituted anisoles
title_sort experimental and theoretical study of the methoxy group conformational effect on 13c chemical shifts in ortho‐substituted anisoles
url http://hdl.handle.net/20.500.12110/paper_07491581_v27_n2_p158_Biekofsky
work_keys_str_mv AT biekofskyrr experimentalandtheoreticalstudyofthemethoxygroupconformationaleffecton13cchemicalshiftsinorthosubstitutedanisoles
AT pomilioab experimentalandtheoreticalstudyofthemethoxygroupconformationaleffecton13cchemicalshiftsinorthosubstitutedanisoles
AT econterasrh experimentalandtheoreticalstudyofthemethoxygroupconformationaleffecton13cchemicalshiftsinorthosubstitutedanisoles
AT dekowalewskidg experimentalandtheoreticalstudyofthemethoxygroupconformationaleffecton13cchemicalshiftsinorthosubstitutedanisoles
AT facellijc experimentalandtheoreticalstudyofthemethoxygroupconformationaleffecton13cchemicalshiftsinorthosubstitutedanisoles
_version_ 1807317571214508032