Question

Name the following compound according to iupac system of nomenclature
$i) C{H_3}CH(C{H_3})C{H_2}C{H_2}CHO$
$ii) C{H_3}C{H_2}COCH({C_2}{H_5})C{H_2}C{H_2}Cl$
$iii) C{H_3}CH = CHCHO$
$iv) C{H_3}COC{H_2}COC{H_3}$
$v) C{H_3}CH{(CH)_3}C{H_2}C{(C{H_3})_2}COC{H_3}$
$vi) {(C{H_3})_3}CC{H_2}COOH$
$vii) OHC{C_6}{H_4}CHO - p$

Answer 1

The root word of all compounds indicates the number of carbon atoms present in the carbon chain. The root word is very important to name the compound as per International pure applied chemistry (IUPAC)

Complete answer:
$i)C{H_3}CH(C{H_3})C{H_2}C{H_2}CHO$
In the given organic compound a total of 6 carbons are there but at the 2nd carbon the methyl group is considered as a secondary prefix, so the root word becomes pent and the compound contains aldehyde as a functional group.
The order of naming as follows
1. Number prefix -2
2. Secondary prefix – Methyl
3. Root word- pent
4. The primary suffix – ane
5. The secondary suffix – al
Iupac name as follows
2-methyl-pentan-1-al
$ii)C{H_3}C{H_2}COCH({C_2}{H_5})C{H_2}C{H_2}Cl$
In the given organic compound a total of 8 carbons are there but the ethyl group is considered as substituent so the root word is Hex. The second substituent is Chlorine and the organic compound contains a functional group called Ketone.
The naming order of Organic compound follows
1. Number prefix -6
2. Secondary prefix – chloro
3. Number prefix -4
4. Secondary prefix –Ethyl
5. Root word- Hex
6. The primary suffix – ane
7. Number prefix- 3
8. The secondary suffix – One
IUPAC name as follows
6-chloro-4- ethyl – Hexan -3 –one
$iii)C{H_3}CH = CHCHO$
In the given organic compound the total four carbons, so root word is but and it is an unsaturated hydrocarbon and the functional group in this compound is an aldehyde
The order of naming as follows
Root word: But
Number prefix -2
The primary suffix- ene
Number prefix -1
The secondary suffix – al
Iupac name of the compound as follows
But-2-ene-1-al
$iv)C{H_3}COC{H_2}COC{H_3}$
The organic compound contains five carbons so the root word is pent and the functional group in this compound is a ketone
Naming order of compound
Root word: Pent
Number prefix – 2, 4
Numerical prefix-di
Secondary suffix – one
Iupac name of the compound as follows
Pent-2, 4-dione
$v)C{H_3}CH{(CH)_3}C{H_2}C{(C{H_3})_2}COC{H_3}$
In the given organic compound total of 9 carbon atoms are there, but the third carbon-containing two methyl groups considered as secondary prefix and on the 5th carbon also having the substituent called methyl group and the functional group present in the compound is a ketone.
Naming order of organic compound
Number prefix – 3, 3, 5
Numerical prefix – tri
Secondary prefix – methyl
Root word – Hex
Primary suffix – ane
Number prefix – 2
Secondary suffix – one
Iupac name as follows
3, 3, 5 –trimethyl-Hexan-2-one
$vi){(C{H_3})_3}CC{H_2}COOH$
The given organic compound containing 6 carbons and one methyl groups at last carbon considered as a substituent and Carboxylic acid is the functional group in the given compound
Naming order of compound
Number prefix – 4
Secondary prefix –Methyl
Root word –pent
Primary suffix – ane
Number prefix -1
Secondary suffix – oic acid
Iupac name as follows
4-methyl- pentan-1-oic acid
$vii)OHC{C_6}{H_4}CHO - p$
The given organic compound cyclic aromatic compound and it is a benzene derivative
At para position, this compound is having aldehyde as a functional group
The numbering order of compound follows
Primary prefix – Cyclo
Root word – Hex
Number prefix – 1, 3, 5
Numerical prefix- tri
Primary suffix – ene
Number prefix -1, 4
Numerical prefix –di
Secondary suffix – al
Iupac name of the compound is
Cyclohex-1, 3, 5- triene – 1, 4 –dial

Note: While numbering organic compounds the priority should be given to the functional group, next priority to the unsaturation like double and triple bond, and last priority for the substituents.