Dear Arpit

Read NCERT and Arihant books for organic. there are solved examples do them. practice it and you will surely feel comfortable in it.

All the best

AKASH GOYAL
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In chemistry, a number of prefixes, suffixes and infixes are used to describe the type and position of functional groups in the compound. The steps to naming an organic compound are:

 1. Identify the parent hydrocarbon chain (The longest continuous chain of carbon atoms)

2. Identify the functional group, if any.. Identify the position of the functional group in the chain 2. Number the carbon atoms in the parent chain. The functional group should end up the least number possible (as there are two ways of numbering—right to left and left to right). The number (in Arabic numerals, i.e. 1, 2, 3....) is written before the name of the functional group suffix (such as -ol, -one, -al, etc.). If the group is a group that can only exist at the end of any given chain (such as the carboxylic acid and aldehyde groups), it need not be numbered. Note: If there are no functional groups, number in both directions, find the numbers of the side-chains (the carbon chains that are not in the parent chain) in both directions. The end result should be such that the first number should be the least possible. In the event of the first numbers being the same for two methods of numbering, the sum of the numbers of the side chains should be made the least possible; for example, 2,2,5-trimethylhexane (2 + 2 + 5 = 9) is preferred over 2,5,5-trimethylhexane (2 + 5 + 5 = 12), as they both start with '2', but the sum of the numbers of the former is less.

 3. Identify the side-chains and number them. Side chains are the carbon chains that are not in the parent chain, but are branched off from it. If there is more than one of the same type of side-chain, add the prefix (di-, tri-, etc.) before it. The numbers for that type of side chain will be grouped in ascending order and written before the name of the side-chain. If there are two side-chains with the same alpha carbon, the number will be written twice. Example: 2,2,3-trimethyl...

 4. Identify the remaining functional groups, if any, and name them by the name of their ions (such as hydroxy for -OH, oxy for =O , oxyalkane for O-R, etc.). Different side-chains and functional groups will be grouped together in alphabetical order. (The prefixes di-, tri-, etc. are not taken into consideration for grouping alphabetically. For example, ethyl comes before dihydroxy or dimethyl, as the "e" in "ethyl" precedes the "h" in "dihydroxy" and the "m" in "dimethyl" alphabetically. The "di" is not considered in either case). In the case of there being both side chains and secondary functional groups, they should be written mixed together in one group rather than in two separate groups.

 5. Identify double/triple bonds. Number them with the number of the carbon atom at the head of the bond (i.e. the carbon atom with the lesser number that it is attached to). For example a double bond between carbon atoms 3 and 4 is numbered as 3-ene. Multiple bonds of one type (double/triple) are named with a prefix (di-, tri-, etc.). If both types of bonds exist, then use "ene" before "yne" e.g. "6 13 diene 19 yne". If all bonds are single, use "ane" without any numbers or prefixes.

6. Arrange everything like this: Group of side chains and secondary functional groups with numbers made in step 3 + prefix of parent hydrocarbon chain (eth, meth) + double/triple bonds with numbers (or "ane") + primary functional group suffix with numbers. Wherever it says "with numbers", it is understood that between the word and the numbers, you use the prefix(di-, tri-)...

Alk is the prefix of the group (Meth, Eth, Prop, etc.)

Family	Structure	IUPAC nomenclature	IUPAC nomenclature for cyclic parent chains (if different from straight chains)	Common nomenclature
Alkyl groups	R—	Alkyl	-	Alkyl
Halogens	R—x (halogen)	Halo'alkane	-	Alkyl halide
Alcohols	R—OH	Alkanol	-	Alkyl alcohol
Amines	R—NH2	Alkanamine	-	Alkyl amine
Carboxylic acids		(Alk + 1)anoic acid	Cycloalkanecarboxylic acid	-
Aldehydes		Alkanal	Cycloalkanecarboxaldehyde	-
Ketones		Alkanone	-	Alk(1)yl Alk(2)yl ketone
Thiols	R—SH	Alkanethiol	-	-
Amides		(Alk + 1)anamide	Cycloalkanecarboxamide	-
Ethers	R1—O—R2	alkoxyalkane	-	Alk(1)yl Alk(2)yl ether
Esters		Alk(1)yl Alk(2)aneoate	Alk(1)yl Cycloalk(2)anecarboxylate	Alk(1)yl (Alk + 1)(2)anoate

When compounds contain more than one functional group, the order of precedence determines which groups are named with prefix or suffix forms. The highest precedence group takes the suffix, with all others taking the prefix form. However, double and triple bonds only take suffix form (-en and -yn) and are used with other suffixes.

Prefixed substituents are ordered alphabetically (excluding any modifiers such as di-, tri-, etc.), e.g. chlorofluoromethane, not fluorochloromethane. If there are multiple functional groups of the same type, either prefixed or suffixed, the position numbers are ordered numerically (thus ethane-1,2-diol, not ethane-2,1-diol.) The N position indicator for amines and amides comes before "1", e.g. CH₃CH(CH₃)CH₂NH(CH₃) is N,2-dimethylpropanamine.