Accession Number : AD0284906

Title :   ANALYSIS OF A2B2 HIGH RESOLUTION NMR SPECTRA. I. FURAN, THIOPHENE AND DISUBSTITUTED BENZENES

Corporate Author : ILLINOIS UNIV URBANA NOYES CHEMICAL LAB

Personal Author(s) : GRANT,DAVID M. ; HIRST,ROBERT C. ; GUTOWSKY,H.S.

Report Date : 22 MAR 1962

Pagination or Media Count : 1

Abstract : The features of certain classes of A2B2 spectra are investigated systematically relative to the parameters involved, and these characteristic spectra are given as an aid to future interpretation. The effects upon the spectra are given as an aid to future interpretation. The effects upon the spectra of the relative signs of the coupling constants are discussed. Examples are provided by the analysis of spectra for the AROMATIC PROTONS IN FURAN, THIOPHENE, 3 SYMMETRICAL ORTHO DISUBSTITUTED BENZENES, 2 NON SYMMETRICAL PARA DISUBSTITUTED BENZENES AND A SYMMETRICAL 4,4'-DISUBSTITUTED BIPHENYL. Better resolution than was obtainable in previous studies permitted a more detailed analysis for compounds cited earlier. In most examples the 24 main spectral lines expected for 4 spin systems of this symmetry were observed. The disubstituted benzenes studied have 2 non-equivalent ortho or meta coupling constants; they are found to differ by as much as 0.6 cps. The spectrum of each of these substituted benzenes can be interpreted with coupling constants all of the same relative sign. (Author)

Descriptors :   *BENZENES, *FURANS, *NUCLEAR MAGNETIC RESONANCE, *SPECTROGRAPHIC ANALYSIS, *THIOPHENES, MATHEMATICAL ANALYSIS, MATRICES(MATHEMATICS), NUCLEAR SPINS, PHENYL RADICALS

Distribution Statement : APPROVED FOR PUBLIC RELEASE