Nomenclature of compounds

The systematic lUPAC nomenclature of compounds tries to characterize compounds by a unique name. The names are quite often not as compact as the trivial names, which are short and simple to memorize. In fact, the lUPAC name can be quite long and cumbersome. This is one reason why trivial names are still heavily used today. The basic aim of the lUPAC nomenclature is to describe particular parts of the structure (fi agments) in a systematic manner, with special expressions from a vocabulary of terms. Therefore, the systematic nomenclature can be, and is, used in database systems such as the Chemical Abstracts Service (see Section 5.4) as index for chemical structures. However, this notation does not directly allow the extraction of additional information about the molecule, such as bond orders or molecular weight. 

The tautomeric structure leads to ambiguities in the nomenclature of compounds in this series. Thus, 5-methyl- and 6-methylbenzo-furoxan denote two different molecules which, because of their interconversion, cannot be isolated separately at normal temperatures. Throughout this review, when we intend to refer to the ambiguous mixture, we shall use the system employing the lowest numbers. The above methyl derivative, for example, will be described as 6-methyl-benzofuroxan regardless of the form adopted in the crystal. When a... 

What Do We Need to Know Already This chapter assumes that we know about atomic structure and electron configurations (Chapter 1), the basic features of energy, and the nature of the Coulomb interaction between charges (Section A). It is also helpful to be familiar with the nomenclature of compounds (Section D) and oxidation numbers (Section K). 

The naming of these three heterocyclic fused (5 5 5) ring systems has been carried out according to the IUPAC system of nomenclature. Some examples are given as follows compound la (Table 1) is named (3-hydroxy-4-methoxyphenylthieno[2,3-3]pyrrolizin-8-one. Compound 15a (Table 2) is dithieno[3,2-3 2, 3 - 1thiophene. Compound 23a (Table 2) is dithieno[3,2-3 2, 3 - 1pyrrole. Compound 20a (Table 2) is dithicno[3,2-3 2, 3 -r/]thiophene-4,4-dio ide. Compound 13b (Table 2) is 3,4-dimethyldithieno[3,2-3 2, 3 -i/]thiophene-7,7-dioxide. Compound 38 (Table 4) is fM, r, r-10-azatricyclo[5.2.1.01 10]deca-2,5,8-triene. Compound 39 (Table 4) is cis,cis, m-10-azatricyclo[5.2.1.01 10]deca-2,8-diene. The nomenclature of compound 40 (Table 4) is 1,4,7 triaza tricy-clo[5.2.1.01,10]decane. 

Nomenclature of Compounds containing one Phosphorus Atom. September 1952. London The Chemical Society. 

FIGURE 2.11 Structures and nomenclature of compounds that serve as auxiliary nucleophiles. Generation of activated esters. Substituted hydroxamic acids are sometimes added to carbodi-imides or other reactions to improve the efficiency of couplings. The additive suppresses side reactions by converting activated species into activated esters (see Section 2.10) before they have time to undergo secondary reactions, p(Me2SO) HOBt 9.30, HOAt 8.70. 

Introduction and Orientation, Matter and Energy, Elements and Atoms, Compounds, The Nomenclature of Compounds, Moles and Molar Masses, Determination of Chemical Formulas, Mixtures and Solutions, Chemical Equations, Aqueous Solutions and Precipitation, Acids and Bases, Redox Reactions, Reaction Stoichiometry, Limiting Reactants... 

To review Up to this point you have learned about the nomenclature of compounds formed from positive and negative ions of various kinds single ions, polyatomic ions, and multivalent ions. 

NOMENCLATURE OF COMPOUNDS WITH SEVERAL FUNCTIONAL GROUPS... 

The nomenclature of compounds listed in this index follows the usage of the authors of the chapters and not necessarily the strict lUPAC or Chemical Abstracts style. However, when a chemical name as used by the authors is widely divergent from accepted usage, the more appropriate name has been marked with an asterisk to alert the user that the index entry may not appear in the text on the page indicated. To keep entries brief, "obvious" details, such as indicated hydrogen in its usual or only possible place, have been omitted. 

Carbohydrate nomenclature impacts on stereochemistry, and on the nomenclature of compounds other than mainstream carbohydrates (e.g., hydroxylactones), often named as modihed carbohydrates in Chemical Abstracts Service (CAS) and elsewhere. For further stereochemical information on carbohydrates, see Chapter 7. 

Rule 13. Coordination of groups in lower functionality than usual. The nomenclature of compounds involving monocoordination of bifunctional groups and the dicoordination of polyfunctional groups, etc., usually can be handled according to the rules previously given. 

Nomenclature of Compounds with Both Double and Triple Bonds... 

The authors thank Prof. R. Verpoorte of the division of Pharmacognosy, State University of Leiden, The Netherlands for his comments on the biosynthetical and cell culture sections and Prof JE. de Groot of the Laboratory of Organic Chemistry of Wageningen University, The Netherlands for his comments on the nomenclature of compounds. 

In order to steer clear of metaphysical speculations about the ultimate nature of matter, Lavoisier avoids any reference to atoms or to minutest particles of matter and proposes, instead, a reformed nomenclature for chemistry, in which the names of compound substances would reflect their elementary composition . In fact, he regards the decomposition of material bodies into the substances of which they are composed as the chief aim of chemistry. Ultimately, however, this proposed reform of the nomenclature of compound substances in terms of their elementary composition forces the question of what is to be regarded as an element . Lavoisier proposes to answer this question by restricting himself to what can be ascertained by strict empirical means. He explains that, [i]f by the name of element, we mean the simple and indivisible molecules that compose bodies, it is probable that we do not know them if, on the contrary, we attach to the name of element or principle of bodies the idea of the last point at which analysis arrives, all of the substances that we have not yet been able to decompose by any means are, for us, to be considered elements. ... 

The electrochemical series is also used in determining the nomenclature of compounds (Section 7.5). 

Table 3-3 The nomenclature of compounds containing bridging groups...

However, a line notation is not suitable for the representation of the cutting and breaking of connectivities between nodes because a line notation originally focuses on the nomenclature of compounds. Therefore, in this article the remaining three methods are considered for the representation of structures in structure generation. 

The nomenclature of compounds containing complex ions is more involved than that of the simple inorganic compounds considered in earlier chapters. We will see first how complex ions are named and then look at the nomenclature of coordination compounds. 

The absolute and relative rate constants of the displacement reactions of carbon-centered radicals with molecules, which are listed in this chapter have been collected from the literature up to 1982. Considering the large number of relevant publications it has been very helpful to find several data compilations already in print. In particular, we would l e to acknowledge the collection of Rate Constants of Aliphatic Carbon-Centered Rascals in Aqueous Solutions by A.B. Ross and P. Neta (Radiation Chemistry Data Center, Radiation Laboratory, University of Notre Dame, NSRDS-NBS) and Liquid Phase Reaction Rate Constants by E.T. Denisov (IFl/PLENUM, New York, 1974, transl. from Russian, Nauka Press, Moscow, 1971). We would also like to acknowledge the help of Dr. Ch.-H. Fischer in many questions concerning the nomenclature of compounds. 

The nomenclature of compounds containing —S— and =8 is unsatisfactory. As stated in the list on p. 50, —SH is denoted by the suffix -thiol (which is also the generic name) or prefix mercapto-, whereas MeS— is methylthio- sulphides, e.g., MeSBu, are named as methylthiobutane or butyl methyl sulphide. Thioketones EE C=S may be named by the suffix -thione (used in the same way as -one, as in MeBu C=8 hexane-2-thione) the prefix is thioxo-. In addition, a prefix thio- is widely used to denote replacement of oxygen by sulphur, particularly for acids and phenols (cf. thioketones and thioxo- also inorganic practice, p. 18). Thiophenol and thiocresol are normally used... 

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