Substitution IUPAC nomenclature

Name each of the following compounds according to substitutive IUPAC nomenclature ... 

Substitutive IUPAC nomenclature names epoxides as epoxy derivatives of alkanes. According to this system, ethylene oxide becomes epoxyethane, and propylene oxide becomes 1,2-epoxypropane. The prefix epoxy- always immediately precedes the alkane ending it is not listed in alphabetical order like other substituents. 

Ethers are named, in substitutive IUPAC nomenclature, as alkoxy derivatives of alkanes. 

Recall from Section 6.18 that epoxides may be named as -epoxy derivatives of alkanes in substitutive IUPAC nomenclature. 

Section 16.1 Ethers are compounds that contain a C—O—C linkage. In substitutive IUPAC nomenclature, they are named as alkoxy derivatives of alkanes. In functional class IUPAC nomenclature, we name each alkyl group as a separate word (in alphabetical order) followed by the word ether. 

Sulfides are sulfur analogs of ethers they contain the C—S—C functional group. They are named as alkylthio derivatives of alkanes in substitutive IUPAC nomenclature. The functional class IUPAC names of sulfides are derived in the same manner as those of ethers, but the concluding word is sulfide. 

In substitutive IUPAC nomenclature, cyanohydrins are named as hydroxy derivatives of nitriles. Because nitrile nomenclature will not be discussed until Section 20.1, we will refer to cyanohydrins as derivatives of the parent aldehyde or ketone as shown in the examples. This conforms to the practice of most chemists. 

The replacement of an electrofugic atom or group at a nucleophilic carbon atom by a diazonium ion is called an azo coupling reaction. By far the most important type of such reactions is that with aromatic coupling components, which was discovered by Griess in 1861 (see Sec. 1.1). It is a typical electrophilic aromatic substitution, called an arylazo-de-hydrogenation in the systematic IUPAC nomenclature (IUPAC 1989c, see Sec. 1.2). 

Diols are almost always given substitutive IUPAC names. As the name of the product in the example indicates, the substitutive nomenclature of diols is similar to that of alcohols. The suffix -diol replaces -ol, and two locants, one for each hydroxyl group, are required. Note that the final -e of the parent alkane name is retained when the suffix begins with a consonant (-diol), but dropped when the suffix begins with a vowel (-ol). 

Ketones may also be named using functional class IUPAC nomenclature by citing the two groups attached to the carbonyl in alphabetical order followed by the word ketone. Thus, 3-methyl-2-butanone (substitutive) becomes isopropyl methyl ketone (functional class). 

Substitutive nomenclature (Section 4.2) Type of IUPAC nomenclature in which a substance is identified by a name ending in a suffix characteristic of the type of compound. 2-Methylbutanol, 3-pentanone, and 2-phenylpropanoic acid are examples of substitutive names. 

In IUPAC nomenclature, benzene is designated as a parent name. Other compounds that contain the benzene molecule may be considered as substituted benzenes. In the case of monosubstitution (the replacement of a single hydrogen), the prefix of the substituent is added to the name benzene. 

The resonance structures of the 2-substituted pyrazole 1-oxides 74 are discussed in Section 1.1.1. According to IUPAC nomenclature, structure 86 is a 1-substituted lH-pyrazole 2-oxide since the rules dictate that when R=H the indicated hydrogen position takes numbering precedence. Other names found in the literature are 1-substituted pyrazole 2-oxides or 1-substituted 2-oxo-1 H-pyrazoles. Frequently the numbering is switched to give the names 2-substituted 2H-pyrazole 1-oxide, 2-substituted pyrazole... 

The resonance structures of the 3-substituted 1,2,3-triazole 1-oxides 456 are discussed in Section 1.1.1. 3-Substituted 1,2,3-triazole 1-oxides 456 are strictly according to IUPAC nomenclature 1-substituted 1H-1,2,3-triazole 3-oxides since when R=H the hydrogen position takes numbering precedence. The alternative, correct name 1-subshtuted 3-oxo-lH-l,2,3-tri-azoles has not been adopted in the literature. In the present review the most commonly used naming is adopted calling structure 456 a 3-sub-stituted 1,2,3-triazole 1-oxide. This naming is accepted by IUPAC, Chem. Abstr. Autonom. 

The position of the substituents is given according to IUPAC nomenclature using the prefixes 1-, 3-, and 5-. Formazans unsubstituted in the 1- and 5-positions and 1,5-dialkyl-substituted formazans are unknown. Aryl or heteroaryl groups are the most common 1,5-substituents. The 3- or meso position can be occupied by a variety of substituents (e.g., aryl, heteroaryl, H, OH, SR, halogen, N02, CN, and alkyl). 

The term enamine is used mainly for classifications of the functional group as an ensemble, but individual compounds are termed with respect to the parent compound usually as amino substituted olefins, i.e. tertiary enamines as (N,iV-dialkylamino)alkenes. The correct IUPAC nomenclature for tertiary enamines is dialkylalkenylamines, i.e. the basic compound in this case is the amine not the alkene. The difference may be demonstrated for two examples 73 is in the first notation l-iV-methylanilino-2-methyl-propene and, in IUPAC notation, iV-methyl-jV-(2-methyl-l-propenyl)aniline. Correspondingly 74 is usually called 2-methyl- 1-pyrrolidinopropene but in IUPAC notation it is jV-(2-methyl-l-propenyl)pyrrolidine. 

Reaction of an a-substituted enolate with an aldehyde or ketone can give two pairs of aldol dia-stereomers, which are conveniently designated as the syn form (17) and the anti form (18), where R2 is part of the parent chain in IUPAC nomenclature (equation 29). For simplicity, only one enantiomer of each pair will usually be shown throughout this section. The synlanti notation for aldol diastereomers has been described in detail by Heathcock.8... 

In this chapter the sections are arranged in accordance with the nomenclature of substitution transformations introduced by IUPAC (1989 c). In some sections homolytic and heterolytic dediazoniations are discussed together, provided that the diazo-nio group can be replaced by a specific group or class of groups homolytically as well as heterolytically. 

IUPAC substitutive nomenclature locants, prefixes, parent compound, and one suffix. 

It is of course possible to name individual radialenes according to IUPAC rules [e.g. per(methylene)cycloalkanes 1-4]. However, the descriptiveness of the term radialene may some day pave its way into the official nomenclature. For substituted [ ]radialenes we have proposed1 a pragmatic numbering system, in which an inner ring is numbered first, followed by an outer ring . The numbering of substituents should follow IUPAC rules. Thus, the hydrocarbon 7 is 4,4-diethyl-5,5-dimethyl[3]radialene, the ester 8 should be called 7-methoxycarbonyl-5,5-dimethyl[4]radialene, the nitrile 9 which can exist in four diastereomeric forms is (6Z,7Z)-6-cyano-5,5,7-trimethyl[4]radialene and the difunctionalized [5]radialene 10 is (7 ,6Z)-7-bromo-6-formyl-6-methyl[5]radialene. 

Lactams are named in several ways. They are named as alkanolactams by the IUPAC substitutive system, such as 3-propanolactam, 4-butanolactam, 5-pentanolactam, and 6-hexano-lactam, respectively, for the 4-, 5-, 6-, and 7-membered rings, respectively. An alternate IUPAC method, the specialist heterocyclic nomenclature system, names these lactams as 2-azetidinone, 2-pyrrolidinone, 2-piperidinone, and hexahydro-2f/-azepi n-2-one, respectively. These lactams are also known by the trivial names fl-propiolactam, a-pyrrolidone (y-butyrolactam), a-piperidone (8-valerolactam), and e-caprolactam, respectively. 

The variety of methods of naming azo compounds which has been in use for many years may lead to considerable confusion, especially when attempts are made to name structural formulas of highly substituted dye molecules with several azo linkages. Furthermore, in regard to the older dye literature, an intuitive interpretation of an author s intention frequently seems more productive than a detailed analysis of the system of nomenclature which he may be using. An effort is made in this chapter to conform to either the IUPAC or the Chemical Abstracts system [la]. 

The IUPAC rules permit alkyl halides to be named in two different ways, called functional class nomenclature and substitutive nomenclature. In functional class nomenclature the alkyl group and the halide (fluoride, chloride, bromide, or iodide) are designated as separate words. The alkyl group is named on the basis of its longest continuous chain beginning at the carbon to which the halogen is attached. 

Although substitutive names of the type just described are preferred, the IUPAC rules also permit ketones to be named by functional class nomenclature. The groups attached to the carbonyl group are named as separate words followed by the word ketone. The groups are listed alphabetically. 

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