Unit 14: applications of organic chemistry
Learning Aim A: understand the structures, reactions, and properties of functional group compounds.
Assignment title: functional group chemistry for designer molecules
Functional groups
Specific atoms bound in a specific order that provide a compound with certain physical and chemical
properties are referred to as functional groups.
A group of atoms or bonds in a substance known as a functional group in organic chemistry is in charge
of the compound's particular chemical processes. No matter which compounds it is a member of, the
same functional group will respond and behave in the same way. Covalent bonds hold the atoms of
functional groups and other molecules together. The alpha carbon is the first carbon atom to join the
functional group, followed by the beta carbon and the gamma carbon. Depending on whether a
functional group is linked to one, two, or three carbon atoms, it can be classified as primary, secondary,
or tertiary.
Classifying functional groups:
• Alkane
• Alkene
• Halogenoalkane
• Alcohol
• Aldehyde
• Ketone
• Carboxylate acid
• Nitrile
• Amine
• Acyl chloride
Halogenoalkanes and their reactions (nucleophilic substitution and elimination)
Haloalkanes and halides are the other names for halogenoalkanes. Halogenoalkanes contain a halogen
atom such as fluorine, chlorine, bromine, and iodine attached to an alkyl group.
There are 3 types of halogenoalkanes:
Primary halogenoalkanes: In primary halogenoalkane, only 1 alkyl group is bonded to the carbon that
carries the halogen atom, for example,
,Secondary halogenoalkanes: In secondary halogenoalkane, the halogenated carbon is connected
directly to 2 alkyl groups, and it may or may not be the same. For example:
Tertiary halogenoalkanes: In tertiary halogenoalkane, the carbon atom that hold the halogen is directly
connected to 3 alkyl groups, and it might be any mix of the same or different. For example:
Reaction
Halogenoalkanes have two reactions and in both reactions the halogenoalkanes is heated in a sodium or
potassium hydroxide solution under reflux.
Nucleophilic substitution of halogenoalkanes
because the hydroxide ions are good nucleophiles, one option is that the halogen atom is replaced by a
–OH group, which then results in an alcohol by a nucleophilic substitution reaction. For example, in this
reaction, propan-2-ol is formed from 2-bromopropane. Propan-2-ol is an alcohol also known as
isopropyl alcohol.
Elimination reaction of halogenoalkanes
If sodium or potassium hydroxide is present in the reaction, the halogenoalkanes go is elimination. For
example, in this reaction, alkene-propene is formed when 2-bromopropane is reacted to sodium
hydroxide (NaOH).
, One hydrogen atom has been taken from one of the end carbon atoms, along with the bromine from
the central one, as can be seen. In all elimination reactions, the molecules being eliminated are on
neighboring carbon atoms, but a double bond is created between them instead.
Commercially important:
• Flame retardants
• Fire extinguishants
• Refrigerants
• Propellants
• Solvents
• pharmaceuticals
Alcohol (primary, secondary and tertiary) and their reactions (oxidation)
Alcohols are compounds which one or more hydrogen atoms have been replaced by an –OH group in an
alkane. There are 3 types of alcohols:
Primary alcohols: In primary alcohol, only 1 alkyl group is linked to the carbon carrying the –OH group.
For example,
Secondary alcohols: In secondary alcohol, the carbon with the –OH group is connected to 2 alkyl groups,
and it may or may not be the same. For example,
Tertiary alcohols: In tertiary alcohol, the carbon atom that holds the –OH group is only connected to 3
alkyl groups, which can be the same or different. For example,