Question

Explain the iupac nomenclature

Answer 1

In chemical nomenclature, the IUPAC nomenclature of organic chemistry is asystematic method of naming organic chemical compounds as recommended[1] by the International Union of Pure and Applied Chemistry (IUPAC). It is published in theNomenclature of Organic Chemistry(informally called the Blue Book). Ideally, every possible organic compound should have a name from which an unambiguousstructural formula can be created. There is also an IUPAC nomenclature of inorganic chemistry.

To avoid long and tedious names in normal communication, the official IUPAC naming recommendations are not always followed in practice, except when it is necessary to give an unambiguous and absolute definition to a compound. IUPAC names can sometimes be simpler than older names, as with ethanol, instead of ethyl alcohol. For relatively simple molecules they can be more easily understood than non-systematic names, which must be learnt or looked up. However, the common or trivial name is often substantially shorter and clearer, and so preferred. These non-systematic names are often derived from an original source of the compound (see § Common nomenclature – trivial names below). In addition, very long names may be less clear than structural 

Answer 2

Answer:

Explanation:

IUPAC rules for naming only alkane

Longest chain rule

Select the longest continuous chain of carbon atoms, which is regarded as parent chain & is given the name of parent hydrocarbon.

If two chains of equal number of carbon atoms is identified, choose the one with maximum number of substituents (side chains) as parent chain.

Lowest number rule

Number the carbon atoms from the end that is nearest to the point of branching. The number which indicates the position of substituent is called locant.

The sum of all the locants should be the lowest.

Identify the substituents

Assign number to each substituents according to its position on the parent chain.

If two substituents are present on same carbon atom, assign them same number.

There should be as many numbers in the name as there are substituents.

Write the name as single word.

While writing the name, use hyphens to separate locant & alkyl groups and commas to separate numbers.

If two or more substituents are present, write them in alphabetical order.

For identical substituents, use prefixes such as di, tri, tetra etc. However, these prefixes should not be alphabetized.

If two different substituents are located at equivalent positions from the teo ends of the parent chain, the numbering is done in such a way that the alkyl group which comes first in alphabetical order gets the lowest number.

IUPAC rules for naming organic compounds having functional groups

First give appropriate prefix & suffix to the functional groups

Groups>C=C<−C≡C−−X−OH−CHO>C=O−OR−COOH−COO−R−NH2−C≡N−NO2—prefix—−—−—halo−—hydroxy−—formyl−—oxo−—alkoxy−—carboxy−—−—amino−—cyano−—nitro−suffix−ene−yne−−ol−al−one−−oicacid−oate−amine−nitrile−

Now, the longest carbon chain is numbered from the end which is nearest to the functional group. Using the appropriate number of functional group, the complete name is written.

In case of polyfunctional compounds, one of the function group is choosen as the principle functional group & the compound is named on that basis. The remaining functional groups are named as substituents using appropriate prefixes. We use following priority in choosing principle functional group

−COOH,−COOR,−CONH2,−CN,−CHO,>C=O,−OH,−NH2,>C=C<,−C≡C−

If two or more functional groups are of same type, they are indicated by using terminology di, tri etc. In such case, full name of parent alkane is written