Functional group chemistry for designer molecules
A: Understand the structures, reactions and properties of functional group compounds.
Functional group chemistry for designer molecules
Functional groups play a subsequent part in the characteristics that the molecules will gain. These
groups are recognised as specified substituents of the atoms that are present in a molecule
(https://en.wikipedia.org/) functional groups help towards determining chemical properties of a
substance along with predictable reactions that may transpire; they are also often used in the
naming of organic compounds; this is through conjoining the parent alkanes and the functional
groups in order to form a systematic nomenclature.
Bonding of carbons and functional groups through covalent bonds:
1. Alpha Carbon – First carbon atom attached to the functional group
2. Beta Carbon – Second carbon atom attached to the functional group
3. Gamma Carbon – Third carbon atom attached to the functional group
The functional groups are categorised into:
1. Primary
2. Secondary
3. Tertiary
,Halogenoalkanes
Halogenoalkanes are compounds where one or more hydrogen atom from an alkane have
been replaced by hydrogen atoms. They fall into different categories dependant on the way
the halogen atom is positioned on the chain of carbon atoms.
Primary Halogenoalkane (1oC):
• The carbon carrying the halogen atom is only attached to one other alkyl group
• There is one single exception to this: CH3Br and other methyl halides can often be
counted as primary halogenoalkanes despite there being no alkyl groups attached to
the carbon that houses the halogen on it.
Figure 1 – An Illustration depicting Primary Halogenoalkanes Bromoethane, 1-chloropropane, 1-iodo-2-
methlypropan
Secondary Halogenoalkane (1oC):
• The halogen is attached to the carbon.
• The carbon with the halogen attached is directly linked to two other alkyl groups
Figure 2 – An
Illustration depicting Secondary Halogenoalkanes 2-bromopropane, 2-chlorobutane
Tertiary Halogenoalkane (1oC):
• The carbon atom attached to the halogen is directly linked to three alkyl groups
which can be any combination of the same or different.
Figure 3 – An Illustration depicting Tertiary Halogenoalkanes 2-bromo-2-methylpropane, 2-chloro-2-
methlypropane
, Halogenoalkanes can be formed from two different processes:
a. Through a chemical reaction of hydrogen halides and alkenes (Nucleophilic
substitution)
• This is a reaction between a nucleophile and a positively charged electrophile. This
reaction results in the leaving group being replaced with an electron-rich compound.
During nucleophilic substitution, the halogen atom is replaced by a -OH group, and
as a result, this forms an alcohol.
• This is done through refluxing and the conditions include, heat, sodium hydroxide
and an echoic solvent.
Figure 6 – An
Illustration depicting Nucleophilic Reaction with 2-bromobutane to make a alkene-propene
Figure 7:8 – An
Illustration depicting Nucleophilic Reaction Mechanism with 2-bromobutane
• The halogen is electronegative and attracts electrons to its structure giving it a delta
negative charge. Since the carbon atom has a delta positive charge, it attracts the lone
pair electrons. This results in the breakage of the halogen-carbon bond, and as a
result, causes the formulation of a bromide Br- ion.
• During the reflux of the 1-Bromo-1, 1 dimethyl ethane, with a solution of ethanol,
water and sodium hydroxide, the -OH will replace the halogen and therefore
producing an alcohol, tert-butanol.
b. Through replacing the -OH function group of an alcohol with a halogen atom
(Elimination reactions)
• This is the separation of atoms in small groups from one substantial molecule.
Halogenoalkanes are able to perform elimination reactions in the form of refluxing,
with the involvement of sodium hydroxide, potassium and heat. Refluxing makes it
possible for the solution to be heated in a controlled way, inhibiting the loss of any
reactants by collecting the vapours in a condenser.
• A halogenoalkane reacts with sodium hydroxide during this chemical reaction. As
displayed in figure 5 below, the hydrogen ion acts as a base and is removed by the
A: Understand the structures, reactions and properties of functional group compounds.
Functional group chemistry for designer molecules
Functional groups play a subsequent part in the characteristics that the molecules will gain. These
groups are recognised as specified substituents of the atoms that are present in a molecule
(https://en.wikipedia.org/) functional groups help towards determining chemical properties of a
substance along with predictable reactions that may transpire; they are also often used in the
naming of organic compounds; this is through conjoining the parent alkanes and the functional
groups in order to form a systematic nomenclature.
Bonding of carbons and functional groups through covalent bonds:
1. Alpha Carbon – First carbon atom attached to the functional group
2. Beta Carbon – Second carbon atom attached to the functional group
3. Gamma Carbon – Third carbon atom attached to the functional group
The functional groups are categorised into:
1. Primary
2. Secondary
3. Tertiary
,Halogenoalkanes
Halogenoalkanes are compounds where one or more hydrogen atom from an alkane have
been replaced by hydrogen atoms. They fall into different categories dependant on the way
the halogen atom is positioned on the chain of carbon atoms.
Primary Halogenoalkane (1oC):
• The carbon carrying the halogen atom is only attached to one other alkyl group
• There is one single exception to this: CH3Br and other methyl halides can often be
counted as primary halogenoalkanes despite there being no alkyl groups attached to
the carbon that houses the halogen on it.
Figure 1 – An Illustration depicting Primary Halogenoalkanes Bromoethane, 1-chloropropane, 1-iodo-2-
methlypropan
Secondary Halogenoalkane (1oC):
• The halogen is attached to the carbon.
• The carbon with the halogen attached is directly linked to two other alkyl groups
Figure 2 – An
Illustration depicting Secondary Halogenoalkanes 2-bromopropane, 2-chlorobutane
Tertiary Halogenoalkane (1oC):
• The carbon atom attached to the halogen is directly linked to three alkyl groups
which can be any combination of the same or different.
Figure 3 – An Illustration depicting Tertiary Halogenoalkanes 2-bromo-2-methylpropane, 2-chloro-2-
methlypropane
, Halogenoalkanes can be formed from two different processes:
a. Through a chemical reaction of hydrogen halides and alkenes (Nucleophilic
substitution)
• This is a reaction between a nucleophile and a positively charged electrophile. This
reaction results in the leaving group being replaced with an electron-rich compound.
During nucleophilic substitution, the halogen atom is replaced by a -OH group, and
as a result, this forms an alcohol.
• This is done through refluxing and the conditions include, heat, sodium hydroxide
and an echoic solvent.
Figure 6 – An
Illustration depicting Nucleophilic Reaction with 2-bromobutane to make a alkene-propene
Figure 7:8 – An
Illustration depicting Nucleophilic Reaction Mechanism with 2-bromobutane
• The halogen is electronegative and attracts electrons to its structure giving it a delta
negative charge. Since the carbon atom has a delta positive charge, it attracts the lone
pair electrons. This results in the breakage of the halogen-carbon bond, and as a
result, causes the formulation of a bromide Br- ion.
• During the reflux of the 1-Bromo-1, 1 dimethyl ethane, with a solution of ethanol,
water and sodium hydroxide, the -OH will replace the halogen and therefore
producing an alcohol, tert-butanol.
b. Through replacing the -OH function group of an alcohol with a halogen atom
(Elimination reactions)
• This is the separation of atoms in small groups from one substantial molecule.
Halogenoalkanes are able to perform elimination reactions in the form of refluxing,
with the involvement of sodium hydroxide, potassium and heat. Refluxing makes it
possible for the solution to be heated in a controlled way, inhibiting the loss of any
reactants by collecting the vapours in a condenser.
• A halogenoalkane reacts with sodium hydroxide during this chemical reaction. As
displayed in figure 5 below, the hydrogen ion acts as a base and is removed by the
