Open AccessNUCLEAR MAGNETIC RESONANCE STUDIES: PART I. THE CHEMICAL SHIFT OF THE FORMYL PROTON IN AROMATIC ALDEHYDES
Author(s) -
R. E. Klinck,
J. B. Stothers
Publication year - 1962
Publication title -
canadian journal of chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.323
H-Index - 68
eISSN - 1480-3291
pISSN - 0008-4042
DOI - 10.1139/v62-165
Subject(s) - chemistry , chemical shift , steric effects , proton , proton magnetic resonance , resonance (particle physics) , aromaticity , solvent , computational chemistry , photochemistry , organic chemistry , nuclear magnetic resonance , molecule , nuclear physics , physics , particle physics
Chemical shift data for the formyl proton in some 30 aromatic aldehydes are reported. It was found that meta- and para-substituted benzaldehydes exhibited this peak in the range 9.65–10.20 δ, while ortho-substituted compounds appear at lower field, 10.20–10.50 δ; the former shifts show an approximate correlation with the Hammett sigma parameter. Evidence for steric inhibition of resonance is presented for some ortho-substituted compounds and some interesting solvent effects are discussed.