Isotopically Modified Compounds

R-8.3.3 Nonselectively labelled compounds

An isotopically labelled compound is designated as nonselectively labelled when the position(s) and the number of the labelling nuclide(s) are both undefined.

Note: When only atoms of an element to be modified are present at the same position in a compound, only specific or selective labelling can result. Nonselectively labelling requires that the element to be modified be at different positions in the structure. For example, CH4 and can only be specifically or selectively labelled with a hydrogen isotope (see R- and R-

R- Nonselectively labelling is indicated in the formula by inserting the nuclide symbol, enclosed in square brackets, directly before the usual line formula with no locants or subscripts.

Examples to R-

R- The name of a nonselectively labelled compound is formed in the same way as the name of a selectively labelled compound but contains neither locants nor subscripts in the nuclide descriptor.

Examples to R-

R-8.3.4 Isotopically deficient compounds

This HTML reproduction is as close as possible to the published version [see IUPAC, Commission on Nomenclature of Organic Chemistry. A Guide to IUPAC Nomenclature of Organic Compounds (Recommendations 1993), 1993, Blackwell Scientific publications, Copyright 1993 IUPAC]. If you need to cite these rules please quote this reference as their source.

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