Suffixes naming alkynes

In naming alkynes the usual lUPAC rules for hydrocarbons are followed and the suffix ane is replaced by yne Both acetylene and ethyne are acceptable lUPAC names for HC=CH The position of the triple bond along the chain is specified by number m a manner analogous to alkene nomenclature... 

The IUPAC Rules are exactly the same for naming alkynes as for naming of alkenes except that die suffix -yne replaces -ene. 

Both double and triple bonds are multiple bonds. Therefore alkynes are unsaturated hydrocarbons, just as alkenes are. To name alkynes and draw their structures, you follow the same rules that you used for alkenes. The only difference is the suffix -yne, which you need to use when naming alkyne compounds. Also, remember to count the number of bonds for each carbon. An alkyne bond counts as three bonds. 

SO that C-atom with the double bond has the smallest possible number. The rules for naming alkynes are the same as for alkenes with the exception that the suffix is -yne. 

The lUPAC names of alkenes use the suffix -ene. Alkynes, which are also unsaturated because they contain one or more carbon-carbon triple bonds, will be discussed in Chapter 7. Unsaturated compounds that contain a benzene ring or structural units that resemble a benzene ring are aromatic hydrocarbons. They will be discussed in Chapter 13. 

Alkynes aie named m much the same way as alkenes using the suffix yne instead of ene... 

The IUPAC names of alkynes are derived from those of the corresponding alkenes by replacing the suffix -ene with -yne. Thus we have... 

The alkynes are hydrocarbons that have at least one carbon-carbon triple bond. The simplest is ethyne, FIO CH, which is commonly called acetylene (20). Alkynes are named like the alkenes but with the suffix -yne. 

This number indicates the number of the first carbon atom that is part of the double/triple bond. (2) The name of longest carbon chain is formed by taking the alkane name, dropping the -ane suffix and replace it by -ene for an alkene or -yne for an alkyne. 

Alkynes are named in much the same way as alkenes, using the suffix -yne instead of -ene. 

Alkynes are similar in many respects to alkenes and are named using the suffix -yne. The simplest alkyne, HC = CH, is often called by its alternative name acetylene rather than by its systematic name ethyne. 

In a hydrocarbon name, the prefix tells how many carbon atoms are in the molecule, and the suffix tells how many carbon and hydrogen atoms are in the molecule. The general formula for alkanes is CnH2n+2, the general formula for alkenes is C H2n, and the general formula for the alkynes is C H2n,2. 

The naming system is extended to include alkenes by changing the suffix from -ane to -ene, and to alkynes by the suffix -yne. A number before the suffix gives the location of the multiple bond. The terminal carbon is that closest to the multiple bond it has priority over branching of the carbon skeleton. 

Alkynes, also known as acetylenes, have a carbon-carbon triple bond functional group (see Figure 11.14). Alkynes are relatively rare in medical settings, so we present them only for the sake of completeness. The simplest alkyne is ethyne, which is more commonly known as acetylene. Alkynes are named by adding the suffix -yne and following the normal IUPAC rules. 

The names of alkenes and alkynes contain the suffixes -ene and -yne, respectively. With some alkenes it is necessary to define the stereochemistry of the double bond ... 

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. 

In the tables on the following pages, the symbols R and R represent hydrocarbons in covalent linkage to the functional group. Many derivatives are named in a similar manner to alkenes and alkynes, but the location and suffix of the functional group is used in place of -ene and -yne. 

Alkynes are named in a manner nearly identical to the naming of alkenes except that the suffix is -yne. The same rules for numbering apply. Compounds with several triple bonds use the suffixes -diyne, -triyne, and so on. For compounds that contain both a double bond and a triple bond, both suffixes are used, as in -enyne. Some examples follow ... 

Alkynes are hydrocarbons with carbon-carbon triple bonds as their functional group. Alkyne names generally have the -yne suffix, although some of their common names (acetylene, for example) do not conform to this rule. The triple bond is linear, so there is no possibility of geometric (cis-trans) isomerism in alkynes. 

Alkynes are named by using the -yne suffix in place of the -ane suffix of alkanes. 

The nomenclature for alkynes involves the use of -yne as a suffix to replace the -ane of the parent alkane. Thus the molecule CH3CH2C=CCH, has the name 2-pentyne. 

The rules for naming an unsaturated hydrocarbon with fewer than four carbon atoms are similar to those for naming alkanes. A two-carbon alkene is named ethene, with the suffix -ene indicating that the molecule is an alkene. A three-carbon alkyne is named propyne, with the suffix -yne indicating that the molecule is an alkyne. 

Chains containing unsaturation are accommodated in substitutive nomenclature by the methods used with alkenes and alkynes (see Section P-31.1 of Ref. 1), i.e. the name of the corresponding saturated chain hydride is modified by replacing the ane ending with ene in the case of a double bond and yne in the case of a triple bond. If there is one of each, the ending becomes en . .. yne with appropriate locants diene is used when there are two double bonds, and so on. In each case the position(s) of unsaturation is (are) indicated by (a) numerical locant(s) immediately preceding the suffix(es). Locants are chosen to be as low as possible. 

Alkynes are named like the alkenes but with the suffix -yne. 

Alkynes are named by using the stem name of the corresponding alkane with a number specifying the location of the triple bond. The numbering convention is the same as that used for double bonds. If more than one triple bond is present, the number of these bonds is indicated by a Greek prefix. The suffix is -yne. 

Alkynes are named like the alkenes except that the suffix -yne is added to the characteristic root. The first member of the series is commonly called acetylene. Its molecular formula is C2H2. It is thermodynamically unstable, decomposing explosively to C(s) and 112(g) high pressures. It may be converted into ethene (also known as ethylene) and then to ethane by the addition of hydrogen. The condensed formulas for several small alkynes are... 

Alkenes contain one or more double bonds. Alkenes, alkynes, and aromatics are unsaturated because they have fewer hydrogen atoms.Alkenes are also called olefins. The suffix used in the naming of alkenes is -ene, and the number roots are those used for alkanes of the same length. 

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. 

Hydrocarbons that contain at least one C=C bond are called alkynes (general formula C H2 2). Because a carbon in a C=C bond can bond to only one other atom, the geometry around each C atom is linear (180°) each C is ip hybridized. Alkynes are named in the same way as alkenes, except that the suffix is -yne. Because of their localized it electrons, C=C and C=C bonds are electron rich and act as functional groups. Thus, alkenes and alkynes are much more reactive than alkanes, as we ll discuss in Section 15.4. 

If the same number for the alkyne functional group suffix is obtained counting from either direction along the carbon chain, the correct systematic name is the one that contains the lowest substituent number. If the compound contains more than one substituent, the substituents are listed in alphabetical order. 

If the functional groups are a double bond and a triple bond, the chain is numbered in the direction that yields the lowest number in the name of the compound. Thus, the lower number is given to the alkene suffix in the compound on the left and to the alkyne suffix in the compound on the right. 

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