There are functional groups that fall under organic chemistry. Today, we will be learning how to name these functional groups and what differentiates them from each other.
Halides:
Halides, as the name suggests, contains elements from the halogen group (which is easy to remember considering they both begin with the same three letters). When naming a halide, one would apply the same rules in naming the parent carbon chain and then would proceed in naming the halogens as side chains.
CH3-CH2-CH2-CH-CH3
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F
F
In the example above, start by:
1. Identifying & naming the parent chain which in this case, would be pentane.
2. Then count the side chain in the lowest possible numbering scheme (double or triple bonds would take priority over this rule). In this example, the number would be 2.
3. Finally take the the halogen, which would be flourine and make it floro (iodine=iodo, bromine=bromo, chlorine=chloro).
4. Put all the elements together: 2 floro pentane
Amines:
An amine includes not only carbons, but a nitrogen as well. Amines can be primary, secondary, or tertiary, depending on the number of carbon chains connected to it.
CH3-CH2-NH-CH3
In the example above, start by:
1. Identifying the side chains connected to the nitrogen which in the example, would be methyl and ethyl.
2. As the nitrogen is located in between the two carbon chains, no numbering is required.
3. Name the amine in alphabetical order: ethyl methyl amine
Amides:
Amides, though also contain a nitrogen, differentiate from amines as they contain a double-bonded oxygen.
O=C-CH2-CH2-CH2-CH3
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NH2
In the example above, start by:
1. Indentifying the parent carbon chain which, in the example, would be a chain of five carbons. Take the prefix of 'penta-' and add '-namide- to it.
2. Name the final product: Pentanamide.
Alcohols:
The functional group of alcohols includes a single bonded '-OH'.
CH3-CH-CH2-CH-CH2-CH3
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OH OH
In the example above, start by:
1. Identifying the number of carbons in the parent chain which, in this case, would be described with the prefix, 'Hexa-'.
2. Number the '-OH's according to the lowest possible numbering scheme and use 'di' when creating the final name as there are two '-OH's.
3. Name the final product: 2, 4 hexadiol.
Aldehydes:
Aldehydes include a carbon on either end, attached to a double-bonded 'O', and therefore, receiving the lowest number.
CH3-CH2-CH2-CH2-CH2-CH2-CH=O
In the example above, start by:
1. Identifying the number of carbons in the parent chain in the example can be described with the prefix of 'Hepta'.
2. Because the 'O' is found on the end of the carbon chain, there is no numbering needed.
3. Add to the prefix, '-nal' to complete the name: Heptanal.
Ketones:
Ketones are similar to aldehydes in the way they have a double-bonded 'O' but differ in the way that the double-bonded 'O' is not found on either end.
CH3-C-CH3
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O
In the example above, start by:
1. Idenifying the number of carbons in the parent chain which in this case, can be described with the prefix 'Prop'.
2. Give the double-bonded 'O' the lowest possible number in the numbering sceme.
3. When you name the compound, and '-none' to it: 2 Propanone.
Carboxylic Acids:
Carboxylic acids contain along with a carbon chain, a double-bonded 'O' as well as an '-OH'.
CH3-CH2-CH2-C=O
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OH
In the example above, start by:
1. Identifying the number of carbons in the parent chain which, in this example, can be described with the prefix 'Buta-'.
2. Add '-noic acid' to the end to create the name: 'Butanoic Acid'.
Ethers:
Ethers have carbon chains that branch off of an 'O'.
CH3-CH2-CH2-O-CH3
In the example above, start by:
1. Identifying the carbon chains attached to the 'O'. They are propyl and methyl.
2. State the carbon chains in alphabetical order and add 'ether': Methyl Propyl Ether.
Esters:
Esters are the product of a carboxylic acid and an alcohol. Therfore, they contain a double-bonded 'O' and another 'O' in addition to a carbon chain.
O=CH-O-CH2-CH2-CH3
In the example above, start by:
1. Identify how many carbons are attached to the carbon that is connected to the double-bonded 'O' and single 'O'. Since there is only one, use the prefix, 'Meth-'.
2. Count the carbons attached to the single-bonded 'O' as a side chain.
3. Name the compound and add '-anoate' to the prefix: Propyl Methanoate.
FOR MORE INFO ON FUNCTIONAL GROUPS, CHECK THESE LINKS OUT!
