Alkane Nomenclature: These are compounds made of carbon and hydrogen formed by single carbon-carbon and carbon-hydrogen bonds. Alkanes have the molecular formula CnH2n+2, where n represents the number of carbon atoms. They are named using prefixes that indicate the number of hydrogens in the chain (meth, eth, prop, but, pent, hex, hept, oct, non, dec, undec), followed by the suffix -ane.
Cycloalkane Nomenclature: They form closed chains or rings. They are classified as monocyclic if they consist of a single ring and polycyclic if they have two or more. They are named analogously to linear hydrocarbons, prefixing the word cyclo- to the name of the linear alkane with the same number of carbons (cyclopropane, cyclobutane, cyclopentane, cyclohexane, etc.).
Alkene Nomenclature: These are hydrocarbon compounds with one or more double bonds between carbon atoms. Their molecular formula is CnH2n, with n ≥ 2. They are named using the same prefixes as alkanes, changing the ending -ane to -ene (ethene, propene, 1-butene).
To name alkenes, the main chain chosen is the longest one containing the double bond, ending in -ene. The position of the double bond is indicated by a locator.
Alkyne Nomenclature: Alkynes are compounds that contain at least one triple bond. With one triple bond, they fulfill the formula CnH2n-2 with n ≥ 2. They are named ending in -yne the name of the alkane with the same number of carbons. The numbering starts from the end that allows assigning the lowest locators to the triple bond.
Benzene and Derivative Nomenclature: Benzene is a hydrocarbon with very different properties than cycloalkenes. They are called aromatic compounds as they are part of the aromatic components present in balms and essential oils. The side chains are named as substituents, ending the name with the word benzene (methylbenzene, chlorobenzene, nitrobenzene).
Alcohol Nomenclature: They are formed by replacing hydrogens (-H) in alkanes with hydroxyl groups (-OH). They are named ending in -ol the hydrocarbon with the same number of carbons, and indicating with a locator the position of the -OH group. When they act as substituents, they are named hydroxy-.
Ether Nomenclature: Ethers are formed by the union of two alkyl (-R) or aryl (-Ar) groups to an oxygen (-O-). The two radicals are named in alphabetical order, ending with the word ether (methyl ethyl ether). The prefix oxy- can also be used between the radicals (methoxyethane).
Aldehyde and Ketone Nomenclature: Aldehydes are named by changing the alkane's ending -o to -al. When there is a priority group, they are named as oxo- or formyl-. The aldehyde group attached to a ring is called -carbaldehyde. In ketones, the ending -o of the hydrocarbon with the same number of carbons is changed to -one. When acting as substituents, like aldehydes, the prefix -oxo is used.
Carboxylic Acid Nomenclature: Carboxylic acids are compounds that contain the carboxylic group, -COOH, at the end of the chain.
The systematic nomenclature names them by prefixing the word acid to the hydrocarbon from which they derive and changing the ending -o to -oic. When attached to rings, the cycle name ends in -carboxylic.
Ester Nomenclature: Esters are formed by the reaction of an acid and an alcohol. The systematic nomenclature names them as salts, ending in -ate the name of the carboxylic acid from which they derive, followed by the name of the radical.
When they act as substituents, they are named as alkoxy carbonyl- and if attached to rings, alkyl carboxylate.
Anhydride Nomenclature: Carboxylic anhydrides result from the condensation with water loss between two carboxylic acid molecules. They are named with the word anhydride followed by the name of the acid from which they come.
There are also mixed anhydrides that come from condensing two different acids.
Acid Halide Nomenclature: These are compounds in which the -OH group of the carboxylic acid is replaced by a halogen -X. They are named as salts of the halogens, changing the acid's ending -oic to -oyl (methanoyl chloride). When they act as substituents, they are called chlorocarbonyl- and if attached to rings, .........carbonyl chloride.
Amine Nomenclature: Amines are compounds formed by substituting one or more hydrogens of ammonia with aryl or alkyl groups. They are classified as primary, secondary, or tertiary depending on whether one, two, or three hydrogens are replaced. They are named ending the name of the alkane from which they derive in -amine.
Amide Nomenclature: Amides are obtained by substituting the -OH group of the carboxylic acid with -NH2. They are named by changing the ending -oic of the carboxylic acid to -amide. The amide group attached to cycles is called -carboxamide and as a substituent -carbamoyl.
Nitrile Nomenclature: They come from substituting the hydrogen of HCN with aryl or alkyl groups. They are named by adding the suffix -nitrile to the name of the alkane with the same number of carbons. When they act as substituents, the prefix -cyano is used and when attached to cycles -carbonitrile.
Nomenclature Book: In this link, you will find the nomenclature book video with more than 500 named molecules and numerous explanatory videos. The first sections deal with substitution nomenclature, ending with bicyclic and heterocyclic systems.
Learn more about nomenclature in organic chemistry........