ISSN:
1573-8353
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract It has been shown that1H,13C,14N,15N,17O, and77Se NMR are very successful techniques for the identification and investigation of potential valence tautomerism in all types of mesoionic compounds. Especially the combined use of14N and15N NMR studies has been shown to be very effective in solving structural problems. From15N NMR it is possible to obtain accurate chemical shifts and spin-spin couplings, whereas the14N NMR spectra provide us with nuclear relaxation and some chemical shift data. In particular14N NMR is very useful for the identification of charged nitrogen atoms in molecules containing non equivalent nitrogen positions. This information is available from the relative14N signal widths, which depend upon the rates of14N relaxation, positively charged nitrogen atoms usually have relatively slow14N relaxation rates thus giving rather sharp NMR signals. Some solid state, CP MAS,13C and15N NMR results are available for comparison with the solution NMR data.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01165049
