Nomenclature radical ions

In this book we use the Nomenclature of Organic Chemistry of the International Union of Pure and Applied Chemistry, 1979 Edition ( Blue book , IUPAC, 1979), the Revised Nomenclature for Radicals, Ions, Radical Ions, and Related Species (IUPAC, 1993), and additional rules applied by the Chemical Abstracts Service for the 1987-1991 Index Guide Chemical Abstracts, 1992). 

IUPAC (1993) Nomenclature of Organic Chemistry. Revised Nomenclature, Ions, Radical Ions, and Related Species, Pure Appl. Chem. 65, 1357 [1.2]. 

IUPAC Commission on Nomenclature of Organic Chemistry, Revised nomenclature for radicals, ions, radical ions and related species (Recommendations 1993), PureAppL Chem., 65, 1357-1455 (1993). 

In the 1979 edition of the lUPAC Nomenclature of Organic Chemistry the term radical was used for several items including explicitly carbenes, and free radicals , i.e., particles with an odd number of electrons (Rule C-81). In the Revised Nomenclature for Radicals, Ions, and Related Species (lUPAC, 1993), the adjective free is not used for the second group of particles. Therefore, the term radical should no longer be used for carbenes. 

N. Lozac h and A.L. Goodson, "Nodal Nomenclature. IL Spedfic Nomendature for Parent Hydrides, ftee Radicals, Ions and Substituents, Angew. Chem. In press. 

As the brief history of conducting polymers tells, initially physicists played the dominant role in research of these materials. Naturally, they borrowed names for the species and phenomena from the nomenclature of their own field, as we have already seen in the case of doping. The terms polaron, bipolaron, and sometimes soliton are frequently seen in the literature on conducting polymers. These terms have been borrowed from solid-state physics. By polaron (Fig. 2a) in connection with CPs we mean radical ion introduced by oxidizing or reducing a conducting polymer molecule. The simple molecular orbital theory shows that the charge of a... 

The radical and the anion, R-N2 and R-N2, derived (formally) from a diazonium ion by addition of one and two electrons respectively, are named as diazenyl ( radical at the end is not necessary ) and diazenide (IUPAC, 1993). The radical derived formally from a diazoalkane by addition of a hydrogen atom (R=N-NH) is named diazanyl . In order to be consistent with the nomenclature of diazonium ions, the name of the parent compound should precede the words mentioned, e. g., benzenediazenyl for C6H5 - NJ (the term phenyldiazenyl radical is, however, used by Chemical Abstracts). 

IR-6.2.4.1 Heteronuclear acyclic parent hydrides in general IR-6.2.4.2 Hydrides consisting of chains of alternating skeletal atoms IR-6.2.4.3 Heteronuclear monocyclic parent hydrides Hantzsch-Widman nomenclature IR-6.2.4.4 Skeletal replacement in boron hydrides IR-6.2.4.5 Heteronuclear polycyclic parent hydrides IR-6.3 Substitutive names of derivatives of parent hydrides IR-6.3.1 Use of suffixes and prefixes IR-6.3.2 Hydrogen substitution in boron hydrides IR-6.4 Names of ions and radicals derived from parent hydrides... 

This section presents names of ions and radicals that can be formally derived from hydrides by the operations of removal or addition of hydrogen atoms, hydride ions or hydrons. A great many ions and radicals can also be named by additive methods, as described in Chapter IR-7. Many simple ions and radicals are named in Table IX, often by both nomenclature types. 

Anionic species take the ending ate in additive nomenclature, whereas no distinguishing termination is used for cationic or neutral species. Additive names of ions end with the charge number (see Section IR-5.4.2.2). In additive names of radicals, the radical character of the compound may be indicated by a radical dot, , added in parentheses and centred, after the name of the compound. Polyradicals are indicated by the appropriate numeral placed before the dot. For example, a diradical is indicated by (2 ) . 

Carbon atoms are the most frequently found radical centers with their electron septet occupying an intermediate position between the carbenium ions and the carbanions. Radicals are often called free radicals, a term that arose from early nomenclature systems in which a radical was a substituent group that was preserved as a unit through a chemical transformation. Thus, the CH3 group as a substituent was known as the methyl radical, so a neutral CHj group became a free radical. The terms radical and free radical are now used interchangeably. Some common examples of radicals include the methyl radical (1), vinyl radical (2), phenyl radical (3), triphenylmethyl radical (4), allyl radical (5), and benzyl radical (6) (Figure 4.1). 

Since the lUPAC nomenclature system relies totally on the pivotal concept of the parent structure to which, in a second sphere, substituents are assigned, it appeared advisable to maintain this division also for the chapters of this book. Thus, we begin with the exposition of the nomenclature rules for parent structures and, in the second chapter, proceed with the discussion of the different types of nomenclature for substituted systems, radicals, and ions in the third chapter specific classes of functional compounds are addressed, followed, in the forth chapter, by the treatment of metal organyls and, in the fifth, of carbohydrates. The concluding sixth chapter takes up once again the construction of the final names of complex compounds including isotopic modifiers and stereochemical descriptors. 

In principle, all radicals and ions can nowadays be named in a uniform and totally systematic manner on the basis of the operational suffixes (and prefixes derived therefrom) compiled in Table 11. Obviously, standardization of the nomenclature for such derived species can be fully congruous only if the names of the underlying parent structures themselves are generated in a thoroughly systematic way, e.g. oxidane, dioxidane, azane, diazane, etc. Hence, in the subsequent sections fully systematic names are always given as well as the conventional trivial/traditional designations. 

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