Transcript Hydrocarbon Derivatives

Functional
groups
The
functional
groups are
atoms or
combinations
of atoms
which
determine the
properties of
organic
molecules.
Substituted alkane with at least one halogen atom
General formula CnH(2n+1)X
Structures & Names
CH3Cl
chloromethane
CH3–CH2 –CH2Br
1- bromopropane
2- iodobutane
CH3–CH–CH2 CH3
I
Alkyl Halides
An alkyl halide (also known as a haloalkane) is an alkane
in which one or more hydrogen atoms have been
replaced with halogen atoms, such as F, Cl, Br, or I
The functional group is R - X, where X represents a
halogen atom.
•Similar in structure , polarity, and reactivity to alcohols
•To name first name the parent hydrocarbon
•Then use the prefix, fluoro, chloro, bromo. or iodo
•Use a position number to indicate the halogen
CH3–CH2–CH2–CH2Br 1- bromobutane PRIMARY 10
CH3–CH2–CH–CH3
Br
CH3
CH3 CH2–C–CH3
Br
2-bromobutane
SECONDARY 20
2-bromo-2-methylbutane
TERTIARY 30
General formula CnH(2n+1)OH Hydroxyl group
•CH3OH Methanol •CH3CH2OH Ethanol
•C3H7OH – two isomers
CH3—CH—CH3
CH3—CH2—CH2OH
OH
TASK: C4H9OH has 4 isomers. Draw the
structures of each isomer giving the name
and class of each one.
•FERMENTATION – sugars (glucose)/yeast/25oC – 35OC
C6H12O6 yeast
2C2H5OH + 2CO2
•HYDRATION OF ETHENE
CH2=CH2 + H2O
CH3CH2OH
Advantage
Fermentation
Hydration
Renewable sources
Low energy
Cheap
Disadvantage
Batch
Slow
Impure/Low yield
High energy
Fast
Pure
Non-renewable
High yield /continuous
Expensive
Examples:
H
H
C
O
H
Methanol CH3OH
H
H
H
H
C
C
H
H
Ethanol C2H5OH
O
H
Depending on the position of the hydroxyl group, an
Alcohol can be primary, secondary or tetiary
HO-CH2- CH2-CH2 – CH3
primary
The hydroxyl group is bonded to a carbon atom that
is bonded to only one other carbon atom
secondary
tetiary
How to name an Alcohol
Step 1 Locate the longest chain that
contains an — OH group attached to one of
the carbon atoms. Name the parent alkane
Step 2 Replace the — e ending of the name
of the parent alkane with — ol
Step 3 Add a position number before the
root name to indicate the location of the
— group OH (Remember to number the main
chain of the hydrocarbon so that the
hydroxyl group has the lowest possible
position number
Step 4 Name and number any other branches
on the main chain. Add the names of these
branches to the prefix
If the functional group occurs multiple times,
place a prefix (di, tri, tetra etc)
Step 5 Put the name together:
prefix + root + suffix
Try this: Name the following alcohol. Identify
it as a primary, secondary or tertiary alcohol
Ethers
Suppose that you remove the H atom from
the - OH group of an alcohol. This would
leave space for another alkyl group to attach
to the oxygen atom.
CH3CH2-OH → CH3CH2-O → CH3CH2-O – CH3
The compound you have just made is called an ether
An ether is an organic compound that has two alkyl
groups joined by an oxygen atom.
The general formula of an ether is R – O – R\
You can think of alcohols and ethers as derivatives
of the water molecule
How to name an Ether
• Choose the longest alkyl group as the
parent alkane. Give it an alkane name
• Treat the second alkyl group (shorter),
along with the oxygen atom as an alkoxy
group attached to the parent alkane
• Name it by replacing the —yl ending of the
corresponding alkyl group’s name with
—oxy
• give it a position number
• put the prefix and suffix together:
• alkoxy group + parent name
Functional groups with C=O
For example the sweet tase of vanilla, spicy scent of
cinnamon have something in common:
- Carbonyl group
Composed of a carbon atom double-bonded to an
oxygen atom
Aldehydes and Ketones
Aldehydes and Ketones both have the carbonyl
functional group
An aldehyde is an organic compound that has a
double-bonded oxygen on the last carbon of the
carbon chain
The general formula for an aldehyde is
These are the first two aldehydes
When a carbonyl group occurs within a hydrocarbon
chain, the compund is a ketone
•An organic compound that has a double-bonded
oxygen on any carbon within a carbon chain
The general formula for a ketone is
groups
How to name an Aldehyde
• Name the parent alkane always give the carbon
atom of the carbonyl group position number 1
• replace the —e at the end of the name of the
parent alkane with — al.
• the carbonyl group is always given position
number 1. therefore you do not need to include a
position number for it.
Carboxylic Acids
You are familiar with one
You sprinkle it over your french fries or salad
Vinegar 5% solution of Acetic Acid in water
The IUPAC name for acetic acid, CH3COOH, is ethanoic acid
Functional group
Amines
Organic compounds with functional group -NH2 – NHR,
or NHR2 is called an amine The letter N refers to the
nitrogen atom the letter R refers to an alkyl group
attached to the nitrogen
H
R
N
H
The general formula for an amine is R– NR2
Primary amine
H
R
N
H
Primary amine has one alkyl group and
two hydrogen atoms attached to the
nitrogen
Secondary amine
R'
R N
H
A secondary amine has two alkyl groups
and one hydrogen atom attached to the
nitrogen
Tertiary amine
R'
R
N
R''
A tertiary amine has three alkyl groups
attached to the nitrogen
How to name an Amine
• Identify the largest hydrocarbon group attached
to the nitrogen as the parent alkane
• Replace the — e at the end of the name with —
amine. Include the position number to show the
position of the functional group
• Name other alkyl group(s) attached to the
nitrogen atom. Instead of position numbers, use
the letter — N to locate the group(s)
• if two identical alkyl groups are attached to the
nitrogen atom, use N,N —
• this is the prefix
• Prefix + Root + Suffix
This process is known as esterification