Straight-Chain Hydrocarbon Nomenclature

The system for naming the straight-chain hydrocarbons is based on an agreed-upon method of retaining the first three or four common names, then using Greek prefixes that indicate the number of carbon atoms in die chain. For isomers, the same system is used, always using the name of the compound that is attached to the chain and the name of the chain. 

Radicals are referred to as hydrocarbon backbones . As an example, isobutane is more properly named methyl propane. Another isomer with a different proper name is isopentane, more properly called methyl butane. Neopentane is also named 2,2-dimethyl propane. 

The following is a list of rules for proper nomenclature of the isomers and their derivatives. 

Find the longest continuous chain and name it as if it were an alkane. 

Identify the number of the carbon atom on the longest chain to which the branch is attached by counting from the end of the chain nearest to the branch. 

Recall the first analogous series of hydrocarbons, the alkanes -a series of saturated hydrocarbons, all ending in -ane. For these 

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The nomenclature of organic chemistry derives from the names of straight-chain hydrocarbons, the most important of which are given in Table S2.2. To name a hydrocarbon ... 

Alkanes are a class of saturated hydrocarbons with the general formula C H2n. -2- They contain no functional groups, are relatively inert, and can be either straight-chain (normal) or branched. Alkanes are named by a series of IUPAC rules of nomenclature. Compounds that have the same chemical formula but different structures are called isomers. More specifically, compounds such as butane and isobutane, which differ in their connections between atoms, are called constitutional isomers. 

Over the years, many people contributed to the development of the field of organic chemistry. To better understand how this science provides so many useful items for our daily use, it is necessary to be familiar with some of the nomenclature of organic chemistry. There are two basic types of hydrocarbon substances, namely, aliphatic and aromatic. There are three basic types of aliphatic hydrocarbon molecules defined by the number of bonds involved in straight linear-chained molecules. If the basic structure of a hydrocarbon molecule is a ring instead of a straight chain, they are known as aromatic hydrocarbons, typified by the benzene ring. 

So far, we have just looked at hydrocarbons that are straight chains. There are many compounds where central carbon atoms are bonded to three or four carbon atoms or other non-hydrogen atoms. For branched-chain hydrocarbons, there are special procedures for naming compounds. To start with, we will only consider saturated hydrocarbons. Once you understand some of the basic rules of nomenclature, we can begin to look at unsaturated hydrocarbons and atoms other than carbon and hydrogen. 

Aliphatic framework molecules most common in organic acids include alkanes (saturated hydrocarbons) and alkenes (unsaturated hydrocarbons). These saturated and unsaturated aliphatic carboxylic acids may be acyclic (straight or branched chains) or alicyclic (aliphatic rings). Acyclic aliphatic monocarboxylic acids are also referred to as fatty acids (Table 1). The first five saturated acids (formic to valeric) of this type are sometimes referred to as short-chain, low-molecular-weight, or volatile fatty acids. Although a nomenclature for these acids has been established by the International Union of Pure and Applied Chemistry (lUPAC), the convention of using the trivial names for the first five saturated acids has remained. Similarly, trivial names are used for the aliphatic dicarboxylic acids (Table 2) that are saturated with two to four carbon atoms (C2-C4) and unsaturated with four carbon atoms (C4). Alicyclic carboxylic acids contain one or more saturated or partially unsaturated rings. These acids most commonly occur... 

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