Prefixes in chemical names

See also Conference proceedings Melting points as analytical data, 266 mer as prefix in chemical names, 232—233 Merriam- Webster s Collegiate Dictionary, 67 meso as prefix in chemical names, 232—233, 238t... 

In chemical names, use (R) and (S), with designated locants when applicable, as prefixes to designate absolute configuration. 

Table 2.3 Numerical Prefixes Used in Chemical Names...

A chemical name typically has four parts in the IUPAC system of nomenclature prefix, locant, parent, and suffix. The prefix specifies the location and identity of various substituent groups in the molecule, the locant gives the location of the primary functional group, the parent selects a main part of the molecule and tells how many carbon atoms are in that part, and the suffix identifies the primary functional group. 

Compounds containing the neutral (formally zwitterionic) group =N2 attached by one atom to carbon are named by adding the prefix diazo- to the name of the parent compound (Rule 931.4), e.g., diazomethane, ethyl diazoacetate. Diazo is a so-called characteristic group appearing only as a prefix in substitutive nomenclature. Chemical Abstracts and Beilstein indexing of diazo compounds is analogous to that mentioned above for diazonium ions and salts, but Diazo compounds is not... 

The written name of a compound includes the names of the elements it contains and information about the numbers of atoms of each element. The elements have to occur in some order, and this order is set by the same guidelines as for the chemical formula (see Section 3-11. Names can contain element names, roots derived from element names, and prefixes indicating the number of atoms of each element. Tables and 3 list the more important roots and prefixes that appear in the names of binaiy compounds. We can summarize the rules for naming binary compounds in three guidelines ... 

Compounds which are considered to be unusually hazardous in a fire context because of their low flash points (below 25°C) or auto-ignition temperatures (below 225°C) are included in the table. The names used are those titles in the text of Section 1 which are prefixed with a dagger. Synonyms may be found either in Section 1 or in the alphabetical index of chemical names and synonyms in Appendix 4. Boiling points are given for those compounds boiling below 50°C. 

The compound headings are those coimnonly used by the U.S. EPA and many agricultural organizations. Positional and/or stmctural prefixes set in italic type are not integral parts of the chemical names and hence ate disregarded in alphabetizing. These include asym-, sym-, n-, sec-, cis-, trans-, a-, P-, y-, o-, m-, p-, N-, S-, etc. 

Knowing the names of the elements and a few basic rules allows us to name simple compounds given the chemical formula. We also can reverse the process. That is, if we know the name of the compound, we should be able to write the chemical formula. The process is straightforward for molecular compounds because prefixes are included in the names. Hence, the formula for sulfin dioxide is SO and carbon monoxide is CO. 

Two systems (246,247) will be discussed in this subsection. The nomenclature of these compounds, as of other borazaromatics, has been a point of controversy. Whereas the authors in this field generally followed the procedure of naming these compounds after the isoconjugate parent aromatic hydrocarbon with prefixes like bora and aza indicating the replacement of a methine group by these atoms, in Chemical Abstracts the principal names are derived by reference to the azaborine system. In this Section and in Section... 

The system of naming now used was devised by the International Union of Pure and Applied Chemistry, abbreviated IUPAC. In the IUPAC system, a chemical name has three parts prefix, parent, and suffix. The parent name tells how many carbon atoms are present in the longest continuous chain the suffix identifies what family the molecule belongs to and the prefix (if needed) specifies the location of various substituent groups attached to the parent chain ... 

---