Download Unit 13: Organic Chemistry

Unit 13: Organic Chemistry
Organic Chemistry
• Organic chemistry is the
study of carbon containing
compounds
• Carbon is unique because
it almost always forms four
bonds
Hydrocarbons
• The simplest organic
compounds, containing
only hydrogen and carbon,
are called hydrocarbons
• Hydrocarbons that have
only single bonds are
called saturated
hydrocarbons
Alkanes
• An alkane is a saturated hydrocarbon with no double or
triple bonds
• Each bond is with another carbon atom or a hydrogen atom
• Straight-chain alkanes have all the carbons bonded in one
long chain
• All alkanes have the formula CnH(2n + 2)
Examples: CH4, C4H10
• To name straight-chain alkanes, use the prefixes in Table P
and add -ane
Practice Problem
Draw the structural formula for each straightchain alkane below and then name them
C2H?
C5H?
C7H?
Alkanes
• Alkanes are ______________ molecules
that will not dissolve in water
• The melting point and boiling point of
alkanes increase with the size of the
molecule due to increasing
_______________________ forces
• Alkanes combust easily with oxygen and
are a common component in fuels
Practice Problem
Match the alkane on the left with its correct
boiling point on the right
CH4
174°C
C5H12
-162°C
C10H22
36°C
Alkanes
• Branched-chain alkanes
have carbons attached to
the central parent chain
• Compounds that have the
same molecular formula
but different structural
formulas are called
isomers
Alkanes
How to name branched-chain alkanes
1. Count the carbons in the parent chain (the longest
chain) and use the corresponding alkane name
2. Number the carbons in the parent chain starting
with the one closest to the branch chain
3. Name each branch with a –yl ending and place it
before the name of the parent chain
4. Use the number of the carbon to which it’s attached
to indicate the branch’s position (if necessary)
Practice Problem
Name the molecule below
Practice Problem
Name the molecule below
Practice Problem
Name the molecule below
Practice Problem
Name the molecule below
Aim: How do we name and draw
structures for alkenes and alkynes??
Do Now:
Draw the structural formulas for two isomers of C4H10
Homework 13.1: Worksheet entitled, “Naming
Hydrocarbons”
Group-Pair Share Problem
Give the structural formula, condensed
structural formula, and molecular formula for
4-propyloctane
Group Pair Share Problem
Give the structural formula, condensed
structural formula, and molecular formula for
2-methylhexane
Group Pair Share Problems
Draw all isomers of pentane
Draw all isomers of hexane
Alkenes and Alkynes
• Hydrocarbons that contain double and triple
bonds are called unsaturated hydrocarbons
• Compounds with double bonds between
carbons are called alkenes
• Alkenes have the formula CnH2n
• Alkynes are compounds with triple bonds
between carbons
• Alkynes have the formula CnH(2n – 2)
Practice Problem
Label the following compounds as alkanes,
alkenes, or alkynes
C3H4
C8H18
C6H12
Alkenes and Alkynes
How to name alkenes and alkynes
1. Count the carbons in the parent chain and use
the corresponding alkane name
Change the ending to –ene or -yne
2. Number the carbons in the parent chain
starting with the one closest to the double or
triple bond
3. Use the number of the carbon where the bond
starts to indicate the bond’s position
Practice Problem
Name the compound below:
Practice Problem
Name the compound below
Group-Pair Share Problem
Name the compounds below:
Aim: How do we name and draw
structures for alkenes and alkynes?
Do Now:
Copy general rules for naming hydrocarbons.
Homework 13.1: Worksheet entitled, “Naming
Hydrocarbons”
Quiz: TOMORROW!! (On drawing hydrocarbon
structures)
Group-Pair Share Problems
Give the structural formula, condensed
structural formula, and molecular formula for
3-octene
Give the structural formula, condensed
structural formula, and molecular formula for
1-butyne
Branched Unsaturated
Hydrocarbons
With unsaturated hydrocarbons that have
attached groups, the longest chain
containing the double (or triple) bond is
considered the parent chain.
Name the following:
This vertex represents
a carbon bonded to
two hydrogen atoms
Carbon atoms are understood to be
at each bond, along with enough
hydrogen atoms so that each carbon
makes four bonds
Structural Formulas
are sometimes
represented by
skeletal structures.
A skeletal structure
usually shows the
carbon framework
of a molecule only
as lines
representing bonds
Name the following:
Hint: Start
by filling in
carbon
and
hydrogen
atoms
Aim: How are functional groups
named?
Do Now:
1. Remove everything from your desk except for:
1. Pen/pencil
2. Reference table
Quiz # 10
Version A
complete
questions:
Version B
complete
questions:
2, 4, 6
3, 5, 7
Cycloalkanes
• Alkanes that are connected in a loop are called closedchain alkanes or cycloalkanes
• They are named by using the prefix cyclo- and the name
of the straight-chain alkane with the same number of
carbons
Aromatic Hydrocarbons
• Benzene is a six carbon
ring with alternating single
and double bonds
• Compounds that contain
benzene rings are called
aromatic compounds
• Compounds without
benzene rings are called
aliphatic
The
hexagon
represents
the six
carbon
atoms and
the circle
represents
the
delocalized
electrons
Practice Problem
Draw C4H6 as a cycloalkene
Functional Groups
• Atoms other than
hydrogen and carbon
occur in organic molecules
as functional groups
• The symbols R and R’
represent bonded atoms
or groups of atoms
Halocarbons
• When any of the halogens
(F, Cl, Br, or I) replaces a
hydrogen, the compound
is called an organic
halide
• They are named by citing
the location of the halogen
and the type of halogen on
the chain
Halocarbons
• Because of the high EN
_________________ of halogens, organic
halides are slightly polar
• They are not polar enough to dissolve in
water
• The boiling points of halocarbons are
slightly higher than the corresponding
alkane
Practice Problem
Name the compound shown below
Group-Pair Share Problem
Draw the structure of 4-iodononane
Aim: How are functional groups
named?
Do Now:
Draw the structures for:
1. 3,3- dimethyl-1-butyne
2. 3-ethyl-2,4,5-trimethyloctane
Alcohols
• –OH is called a hydroxyl group (not to be confused with
OH-!)
• When a hydroxyl group is attached to an organic
molecule it is called an alcohol
• Alcohols are named by adding –ol to the parent chain and
using a number to indicate the location
Alcohols
• Alcohols have hydrogen
bonding and are much
more polar than their
parent alkanes
• Alcohols with five carbons
or less are completely
soluble in water
Group-Pair Share Problem
Draw the structural formula for 1-butanol
Practice Problem
Name the compounds below:
Ethers
• An ether is an organic compound containing an oxygen
atom bonded to two carbon atoms
• Ethers are named by listing the two groups attached
before the word ether
• If the two groups attached are the same the ether is
named by putting di- in front
Practice Problem
Draw the structure of methylpropyl ether
Practice Problem
Name the compound below
Organic Joke
Two hydrocarbons were in the cafeteria having lunch and talking.
One hydrocarbon brings up “Methyl Ethyl” the school gossip.
Methyl Ethyl had a reputation for causing problems between
the hydrocarbons.
The two hydrocarbons finished their lunches and started to head
to their next class.
One hydrocarbon turns to the other and says, “Yeah that Methyl
Ethyl is a bad egg, I don’t like her.”
The other hydrocarbon says, “Yeah, I don’t like Methyl Ethyl
Ether”
Carbonyl Compounds
• The arrangement in which
an oxygen atom is double
bonded to a carbon atom
is called a carbonyl
group
• Many functional groups
are based around a
carbonyl group:
1.Aldehydes
2.Ketones
3.Carboxylic Acids
4.Esters
5.Amides
Aldehydes
• An aldehyde is an organic
compound with a carbonyl
group located on a
terminal carbon
• Aldehydes are named by
adding –al to the name of
the parent chain
• Aldehydes are polar, but
slightly less so than
alcohols or amines
Practice Problem
Draw the structure of propanal
Group-Pair Share Problem
Name the compound below:
Ketones
• A ketone is a compound
in which the carbonyl
group is on a central
carbon
• Ketones are named by
adding –one to the parent
chain and using a number
to indicate the position of
the oxygen
• Ketones are slightly polar
Practice Problem
Name the compound below:
Group Pair Share Problem
Draw the structure of 2-hexanone
Aim: How are functional groups
named?
Do Now:
Draw the structural formulas for:
1. 3-heptanone
2. 3,3-diethyl-2,5-dimethylnonane
3. 1,1,1,2- tetrabromobutane
Carboxylic Acids
• Carboxylic acids, also
called organic acids, have
a carbonyl group bonded
to a hydroxyl group (called
a carboxyl group)
• They are named with the
suffix –oic acid
• They are very polar, weak
acids
Practice Problem
Name the compound below:
Group Pair Share Problem
Draw the structure of propanoic acid
Esters
• A compound formed by
replacing the hydrogen in
a carboxyl group with a
hydrocarbon is called an
ester
• An ester is named by
naming the hydrocarbon
group followed by the
name of the acid but
changing –oic acid to –
oate
Practice Problem
Name the compound below
Group Pair Share Problem
Draw the structure of methyl butanoate
Group Pair Share Questions
Name the following compounds:
Amides
• When the hydroxyl group
of a carboxylic acid is
replaced with a nitrogen
atom, the result is an
amide
• Amides are named by
adding –amide to the
parent chain
Practice Problem
Draw the structure of methanamide
Practice Problem
Name the compound below
Amines
• Amines contain nitrogen
atoms bonded to carbon
atoms
• They are named with the
suffix –amine
• Amines are slightly less
polar than alcohols
• They often have strong,
offensive odors (like dead
fish)
Group-Pair Share Problem
Name the compound below
Practice Problem
Draw the structure of ethanamine
Amino Acids
• Amino acids have an
amine group and a
carboxylic acid
• They can bond together
in long chains to form
proteins and are
essential for all life
Substitution Reactions
• A substitution reaction is one in which one atom or
group of atoms is replaced by another atom or group of
atoms
• The most common organic substitution reaction is when a
hydrogen is replaced by a halogen
Practice Problem
Write a possible reaction between chlorine
and propane
Addition Reactions
• Addition reactions are when a double or triple bond is
broken by the addition of atoms to both sides of the bond
• They are essentially the reverse of elimination reactions
Practice Problem
Write the following reaction: HCl is added to
2-hexene
Practice Problem
Write the following reaction: I2 is added to
propyne
Group Pair Share Problem
Explain why alkanes do not undergo addition
reactions.
Esterification Reactions
In an esterification reaction, an organic acid and an
alcohol combine to form an ester and water
Practice Problem
Write the reaction between ethanoic acid and
1-butanol and name the product
Practice Problem
Write the reaction for the synthesis of methyl
ethanoate
Combustion Reactions
• In a combustion reaction, oxygen combines with
hydrocarbons releasing energy in the form of heat and
light
• The products are always CO2 and H2O
Practice Problem
Write the reaction for the combustion of
propane
Fermentation
• The process in which glucose is broken down into ethanol
is known as fermentation
• Yeasts and some bacteria ferment glucose to produce
ethanol, carbon dioxide, and energy
Saponification
• The reaction of a triglyceride, which is a triple ester, with
a base is called saponification
• The product of the reaction, an organic salt, is soap
Polymerization
• Polymers consist of smaller molecules bonded
together by a series of chemical reactions
• Plastics, synthetic fibers, and rubber are all
examples of polymers
• The reaction in which small organic units, called
monomers, are bonded together into a very
large molecule is called a polymerization
reaction
Polymerization
Polymerization
Group Pair Share Questions
Classify the following compounds as an alcohol,
carboxylic acid, aldehyde, ketone, ester, or
ether.
Group Pair Share Questions
Name or draw the following compounds:
Group Pair Share Questions
Draw structural formulas for the following
compounds:
Butanoic
acid
2,2-dichloro-1,1difluoropropane
3,4-dimethylpentanal
2,3-butanediol