NMR Spectral Chromatography: A Powerful New Tool for Structure Determination.
Abstract
A new technique is described which radically simplified complex nuclear magnetic resonance spectra and markedly increases their information content. Through the use of a unique chemical additive in a sample solution, overlapping spectral peaks are separated, coincidental resonances are dispersed and the entire spectrum remarkably simplified as a result of induced spectral shifts. The additive is a fluorinated rare earth chelate, Eu(fod)3, which is believed to represent the optimum combination of lanthanide metal and organic ligand for use as a shift reagent. Its effect on an NMR spectrum is to 'chromatograph' it by causing spectral absorptions to move to different extents along the 'spectral chromatogram'. The value of 'NMR Spectral Chromatography' is demonstrated by the analysis of a number of complex, misleading and, in some cases, unresolvable spectra. Useful relationships between molecular structure and shifting patterns are pointed out and used in making structural assignments. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1972
- Accession Number
- AD0739885
Entities
People
- Martin A. Berwick
- Roger E. Rondeau
Organizations
- Air Force Research Laboratory