Multiple functional groups, naming

Nomenclature based on a parent term with an appended suffix accounts for most natural product names. However, as related compounds are identified, or even when a suffix has to denote multiple functional groups, a variety of modifying terms can be employed. For example, the common prefix nor- denotes the removal of a skeletal atom from the parent structure the loss of two or more skeletal atoms is indicated by combining an appropriate numerical prefix with nor- , e.g., dinor- , trinor- (Giles 1999). Table 1.2 lists additional examples of commonly encountered modifying terms. 

Classes of compounds are defined by the functional group. There are many common names and functional group names. Multiple names are possible. 

Number the carbon chain giving preference to the functional group named by a suffix, then multiple bonds (carbon-carbon double bonds take priority over triple bonds when making a choice is necessary), then groups named with prefixes. 

Before we start with a systematic discussion of the syntheses of difunctional molecules, we have to point out a formal difficulty. A carbonmultiple bond is, of course, considered as one functional group. With these groups, however, it is not clear, which of the two carbon atoms has to be named as the functional one. A 1,3-diene, for example, could be considered as a 1,2-, 1,3-, or 1,4-difunctional compound. An a, -unsaturated ketone has a 1.2- as well as a 1,3-difunctional structure. We adhere to useful, although arbitrary conventions. Dienes and polyenes are separated out as a special case. a, -Unsaturated alcohols, ketones, etc. are considered as 1,3-difunctional. We call a carbon compound 1,2-difunctional only, if two neighbouring carbon atoms bear hetero atoms. 

Multiple anions are named by using the suffixes -diide , -triide , etc., with such locants as may be necessary, and without eliding terminal e . No other suffixes denoting functional groups may be used with -ide endings functional groups must be indicated by prefixes, as in (194)-(200). 

Acrylic polymers are also important in the preparation of other classes of adhesives, especially pressure sensitive adhesives. This discussion will be limited to adhesives that cure by the reaction of unsaturated acrylic functional groups. These adhesives are also sometimes termed Methacrylate , Methacrylic or Structural Acrylic adhesives. This is consistent with the long-standing habit of organic chemists to assign multiple names to the same substance. 

Metallocene derivatives may be named by either standard organic suffix (functional)7 or prefix nomenclature. Substituents are given the lowest numerical locants in the usual manner on the equivalent cyclopentadienyl rings of the ocene entity. The first ring is numbered 1 to 5 and the second ring is numbered V to 5. In metallocenes composed of multiple ocene groupings the cyclopentadienyl rings are further numbered 1" to 5", V" to 5", etc. The radical names -ocenyl, -ocenediyl, -ocenetriyl, etc. are used. For examples see Table 25. 

It is normal British practice to place the numeral referring to the position of a molecular feature (i.e., its locant) immediately before the syllable it qualifies. American usage is more variable (although the same procedure is followed in cases where confusion or ambiguity might result) it is common to find the locant for a multiple bond or for the principal functional group at the beginning of the name (or immediately... 

Alkynes contain one or more triple bonds. They are named in a similar way to alkenes. The suffix used for alkynes is -yne. Ethyne is often called acetylene. Alkynes with one triple bond have the general formula Cn 2n-2-Multiple triple bonds are named using -diyne, -triyne, etc. The infix -ynyl- is used for functional groups composed of alkynes after the removal of a hydrogen atom. 

Use of hyphens single- and multiple-word names. The general rule in such cases is to determine whether the principal functional group is itself an element or compound. If it is, then the name is written as a single word if it isn t, then the name is written as multiple words. For example, methylbenzene (one word) is correct because the parent—benzene—is itself a compound. Diethyl ether, however, is written as two words because the parent—ether—is a class name rather than a compound name. Some further examples are shown below. 

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