Premium
Deuterium isotope effects as evidence for substituent perturbation of the π‐electron frame in benzanilides
Author(s) -
MoralesRíos Martha S.,
PérezAlvarez Víctor,
JosephNathan Pedro,
Zepeda L. Gerardo
Publication year - 1994
Publication title -
magnetic resonance in chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.483
H-Index - 72
eISSN - 1097-458X
pISSN - 0749-1581
DOI - 10.1002/mrc.1260320506
Subject(s) - chemistry , deuterium , kinetic isotope effect , isotope , substituent , nitrogen , nitrogen atom , conjugated system , computational chemistry , crystallography , medicinal chemistry , atomic physics , organic chemistry , nuclear physics , physics , polymer , group (periodic table)
Deuterium isotope effects on 13 C nuclear shielding, n ΔC(D), transmitted across a D‐labelled nitrogen atom were investigated for a series of para ‐substituted benzanilides. The two two‐bond isotope shifts, 2 ΔC(D) are perturbed essentially in a trough‐bond manner by change of the contribution of mesomeric structures. The magnitudes of 2 Δ(CO) and 2 Δ(C‐1′) are found to be mutually interdependent as evidenced by the linear relationships between the average values of 2 Δ(CO) and 2 Δ(C‐1′) with 1 H(NH) chemical shifts and with 15 N SCS. This behaviour is interpreted as resulting from a cross‐conjugated transmission pathway involving the carbons sharing the D‐labelled nitrogen.