Tellurium-125 nuclear magnetic resonance compounds

Detailed studies of the H, 13C, 77Se, and 12STe nuclear magnetic resonance (NMR) have been carried out on the strained bis-tricyclic selenium- and tellurium-bridged compounds 21-24 <2000TL6157, 2000J(P2)725>. 

CHEC-II(1996) possessed little novel nuclear magnetic resonance (NMR) information, since nearly all papers cited proton and carbon spectra to characterize the compounds. Nevertheless, in the last decade, considerable attention has been focused on the Se and Te NMR. Proton and carbon shifts were already reviewed in CHEC-II(1996) only some examples to complete the understanding of the influence of selenium or tellurium will be herein considered. 

A nuclear magnetic resonance study ( H, Te) of these reaction mixtures established that ketonyl tellurium trichlorides and diketonyl tellurium dichlorides are present. The easily crystallized and less soluble compounds were isolated. Contrary to Morgan s claim, ethyl methyl ketone did react to give bis[2-oxo-l-butyl] tellurium dichloride albeit in very low yield. Alkyl ethyl ketones and tellurium tetrachloride produced very low yields of bis[3-oxo-2-alkyl] tellurium dichlorides. Cyclooctanone and tellurium tetrachloride in refluxing carbon tetrachloride gave bis[2-oxocyclooctyl tellurium dichloride (m.p, 174°) in 40% yield . 

Figure 2 (A) chemical shift ranges of selected selenium functionalities (excluding metal complexes). (B) Se chemical shift ranges of compounds containing C=Se groups (excluding metal complexes). Reproduced by permission of John Wiley and Sons from Duddeck H (1996) Sulfur, selenium and tellurium NMR. In Grant DM and Harris RK (eds) Encyclopedia of Nuclear Magnetic Resonance, pp 4623-4635. Copyright 1996. John Wiley Sons.

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