Functional compounds replacement nomenclature

Current IUPAC and Chemical Abstracts nomenclature has been employed in this index with the former given preference. Substitutive nomenclature has been given preference over radicofunc-tional, additive, subtractive, conjunctive or replacement nomenclature, except where this becomes unwieldy. With many bicyclic and polycyclic compounds bearing heteroatoms, standard bicyclic or polycyclic oxa, aza, and thia replacement nomenclature has often been used. With certain functional groups, where the names are rather complex and probably not familiar to most organic chemists, such as ylides, those compounds have simply been named as sulfur, tellurium and arsonic ylides. Metal catbenes have been treated similarly. With more complex functionality and many heterocycles, the Beilstein Commander Crossfire nomenclature system has been used with certain modifications. 

Parent Acid Names Used in Functional Replacement Nomenclature of Phosphorus and Arsenic Compounds... 

The name in Example 4 regards the compound as derived from arsonic acid, by substitution of a phenyl group for the hydrogen atom bound directly to arsenic. The name in Example 5, in addition to the hydrogen substitution, involves functional replacement nomenclature (Section IR-8.6). 

The term "heteroatom" applies to any atom other than carbon or hydrogen. It is common for heteroatoms to appear in locations that are inconvenient to name following basic rules, so a simple system called "replacement nomenclature" has been devised. The fundamental principle is to name a compound as if it contained only carbons in the skeleton, plus any functional groups or substituents, and then indicate which carbons are "replaced" by heteroatoms. The prefixes used to indicate these substitions are listed here in decreasing priority and listed in this order in the name ... 

Substitution means the replacement of one or more hydrogen atoms in a given compound by some other kind of atom or group of atoms, functional or nonfunctional. In substitutive nomenclature, each substituent is cited as either a prefix or a suffix to the name of the parent (or substituting radical) to which it is attached the latter is denoted the parent compound (or parent group if a radical). 

Similarly, with exocyclic O-PACs, substitutive nomenclature and common suffixes are used to describe the O-atom compounds formed when an H-atom on a PAH is replaced by another atom or functional group, e.g., 6-hydroxybenzo[ ]pyrene, XIX, or 2-methoxychrysene, XX ... 

The prefix "1" in Ihe name of 1-propanol indicates that the replacement of H with OH has occurred at one of Ihe "outer" carbon atoms rather tlian the "middle" carbon atom a different compound called 2-propanol (also known as isopropyl alcohol) is obtained if Ihe OH functional group is attached to the middle carbon atom. Ball-and-stick models of 1-propanol and 2-propanol are presented in Figure 2.28 . As you will learn in Cliapter 25, the nomenclature of organic compounds provides ways in which we can unambiguously define which atoms are bonded to one another. 

---