Oxygen-17 and selenium-77 nuclear magnetic resonance of carbonyl and selenocarbonyl compounds. Correlation of oxygen-17 and selenium-77 chemical shifts

Abstract

The ⁷⁷Se, ¹⁷O, and ¹³C n.m.r. spectra of some carbonyl and selenocarbonyl compounds were studied. The ⁷⁷Se chemical shifts are found to be dominated by the local paramagnetic screening term. δ(⁷⁷O), δ(⁷⁷Se), and ¹J(⁷⁷Se–¹³C) are shown to be affected by the ring size of the molecules. δ(⁷⁷Se) and δ(¹⁷O) of corresponding compounds show excellent correlation and a comparison of them indicates that the bond order terms of CSe and CO, as well as their trends of variation, are practically identical.