The Use of Shift Reagents in NMR Studies of Chemical Exchange.

Abstract

It is shown that paramagnetic 'chemical shift reagents' can be useful in the measurement of chemical exchange rates by nmr methods. The rare earth complexes M(fod)3, with their higher solubility and relatively small line-broadening, were found to be best suited for the purpose. The internal rotation of amides was studied in solutions of the Eu(fod)3 complex, which increases the N-methyl chemical shift several fold and thereby raises the coalescence temperature by as much as 50C. The chief drawback of the method is the relatively high temperature at which the shift reagents have to be used to avoid objectionable line-broadening. (Author)

Document Details

Document Type
Technical Report
Publication Date
Mar 20, 1972
Accession Number
AD0739737

Entities

People

  • H. N. Cheng
  • Herbert S. Gutowsky

Organizations

  • University of Illinois Urbana–Champaign

Tags

DTIC Thesaurus Topics

  • Chemical Shifts
  • Coalescence
  • High Temperature
  • Measurement
  • Motion
  • Rotation
  • Solubility

Fields of Study

  • Chemistry

Readers

  • Analytical Chemistry
  • Circadian Sleep-Wake Regulation and Chronobiology
  • Systems Analysis and Design