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Organic
Introduction
• Two Group 14 elements, carbon and
silicon, form the basis for most natural
substances.
• Silicon, with its great affinity for
oxygen, forms chains and rings
containing Si-O-Si bridges to produce
silica and silicates that form the basis
for most rocks, sands, and soils.
Silicon may be the most important
element in the geological world.
Carbon
• Carbon has the unusual ability of bonding to
itself to form long chains or rings of carbon
atoms.
• Carbon forms strong bonds to other
nonmetals such as hydrogen, nitrogen,
oxygen, sulfur, and the halogens.
• Several million (11 million-plus) are known,
and the number continues to grow rapidly.
• Carbon is the most important compound to
the biological world.
Organic Chemistry
• Organic Chemistry is the study of carboncontaining compounds and their
properties.
• Oxides and carbonates that contain
carbon are not considered to be organic,
they are inorganic.
• The original distinction between organic
and inorganic was based on whether a
compound was produced by living things.
• Organic chemistry plays a vital role in our
quest to understand living systems.
• Industrial organic chemistry produces
synthetic fibers (nylon, rayon), plastics,
rubber (latex) explosives, artificial
sweeteners, vinegar and pharmaceuticals
that are such an important part of modern
life.
• The energy on which we rely so heavily
on to power our civilization is based
mostly on organic materials found in coal
and petroleum.
Saturated and Unsaturated Hydrocarbons
• Hydrocarbons are compounds
composed of carbon and hydrogen.
• Saturated hydrocarbons contain
carbon-carbon bonds that are all single
bonds (each carbon is bonded to
four atoms).
• Unsaturated hydrocarbons contain
carbon-carbon multiple bonds and can
react with additional atoms.
•
Saturated means it is “full of hydrogen”
•
Unsaturated is “missing hydrogens” because of the
double/triple bonds.
H
H
H
C
C
H
H
H
H
C
H
C
H
C
C H
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rights reserved
Hydrocarbons
7
Root words
Meth
# of C
atoms
1
Hex
# of C
atoms
6
Eth
2
Hept
7
Prop
3
Oct
8
But
4
Non
9
Pent
5
Dec
10
So for example
H HHH
H-C-C-C-C-H
H HHH
butane
H HHHHHHH
H-C-C-C-C-C-C-C-C-H
H HHHHHHH
octane
H HH
H
H-C-C-C-H
H-C-H
H HH
H
propane
methane
Molecular Formulas
• Alkanes always have the molecular formula of:
• CxH2x+2
• 2 H on every C except the end, they get 3
• Hexane• C6H14 molecular formula
Lewis Dot, or
Structural Formula
HHHHHH
H-C-C-C-C-C-C-H
HHHHHH
Skeleton Formulas
• Drawing Lewis Dot structural formulas for
long organic compounds can get rather
tedious.
• So organic has shortened it
• They don’t write the C’s or the H’s
• You draw a jagged line, at each corner there is
a Carbon
• Assume all extra spaces are filled with H
For Example
Heptane, C7H16
HHHHHHH
H-C-C-C-C-C-C-C-H
HHHHHHH
=
Nonane, C9H20
HHHHHHHHH
H-C-C-C-C-C-C-C-C-C-H
HHHHHHHHH
=
Isomers
• Isomers- compounds with the same
molecular formula but different structural
formulas
• Different structural formulas mean it has
different properties
• Butane is the first alkane with a possible
isomer
HHHH
=
H-C-C-C-C-H
HHHH
H
H
H
or
H-C- C - C-H
Both are C H
H HCH H
H
4
10
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rights reserved
Butane
14
Naming Isomers
• Name the longest chain possible.
• As a prefix name the chain attached with –
yl on the end and give the number of the
carbon atom it is attached to
1
6
4
2
3
Longest Chain
5
7
3 ethyl
heptane
•It could also be 5 ethyl heptane if you started
numbering from the other side, when given an option
always go with the Lower number!!!
Name this molecule
And give its molecular formula
4 ethyl octane
C10H22
4 propyl decane
C13H28
Cyclic Hydrocarbons
• A hydrocarbon that is a ring instead of a
chain. To name it, give it the prefix “cyclo-”
• Molecular Formula
• Subtract 2 H from CxH2x+2
• CxH2X
• cyclobutane
HH
H-C-C-H
H-C-C-H
HH
C4H8
Name the following compounds
and give their formula
cyclohexane
cycloheptane
C6H12
C7H14
cyclooctane
cyclodecane
C8H16
C10H20
Name and give the formula
Methyl cyclohexane
C7H14
Alkenes
• Contain a double bond
• They get the suffix “-ene” and the number of
the carbon atom the double bond is on
(lowest number)
• Molecular formula
• Subtract 2 H for each double bond from
Skeleton fomula
CxH2x+2
1 butene
H
H H
H-C=C-C-C-H
H H H
C4H8
Alkynes
• Contain a triple bond
• They get the suffix “-yne” and the number of the carbon atom
the triple bond is on. Molecular formula
• subtract 4 H for each triple bond from CxH2x+2
Skeleton fomula
H
H H
H
H H
2 pentyne
H-C-C=C-C-C-H
C5H8
Name and give the formula for
these compounds
2 hexene
C6H12
Cyclopentane
C5H10
3 methyl nonane C10H22
ethyne (commonly known as acetylene)
C2H2
3 methyl 1 pentene
C6H12
Name and give the formula for
these compounds
2 heptene C7H14
Cyclopentene
C5H8
cyclopropane
C3H6
1 butyne
C4H6
3 ethyl 1 hexene
C8H16
Doubles and triples
• If you have two of the same thing put “di”
in front of it
• If you have three of the same thing put “tri”
in front of it
Examples
2,3 hexadiene
C6H10
3,4,4 trimethyl heptane
C10H22
Multiple groups on a chain
• Name each and put them in alphabetical order
3, 4 diethyl 2 methyl
1 heptene
C12H24
Common functional groups
Functional Groups
• Atoms other than hydrogen or carbon
covalently bonded to a carbon atom in an
organic molecule.
• Most commonly oxygen, nitrogen, or the
halogens.
• The presence of a functional group
drastically changes the chemical
properties of a molecule.
Different Functional groups
with a 2 carbon chain
• Ethane- gas (found in natural gas)
• Ethanol- grain alcohol (drinkable)
• Ethanoic acid- vinegar
• Diethyl ether- starting fluid
• Chloro fluoro ethane (CFC’s used as
refrigerants)
• Ethanal- foul smelling liquid (similar to
formaldehyde)
Halogenated Hydrocarbons
• Hydrocarbons with halogens attached
• Before the main chain name the halogen as
either fluoro, chloro, bromo or iodo and give
its number
• For each halogen subtract 1 H
Cl
1,3-dichloro cycloctane
C8H14Cl2
Cl
Practice
F
2 fluoro 1 butene
C4H7F
Br
Br
2,5-dibromo 3-ethyl
4-methyl heptane
C10H20Br2
Alcohols
• Hydrocarbons with an –OH attached
• To name it, give it the suffix –(an)ol and the number
the OH is attached to
• Normally you subtract one H from the main group
and put an OH on the end (to signify it is an alcohol)
H
O
C2H5OH
Ethanol
OH
C3H7OH
2 propanol
Commonly
Isopropanol or
Rubbing alcohol
Aldehydes
• Hydrocarbons with a =O on the outer
edge of the chain
• (most have a foul stench, like
formaldehyde or methanal)
• To name it add the suffix “–al”
• For the formula subtract 2 H and add O
=O
O=
hexanal
C6H12O
octanal
C8H16O
Ketones
• Hydrocarbons with a =O not on the edge of
the compound
• To name it add the suffix “–one”
• For the formula subtract 2 H and add O
O=
O=
cyclopropanone
C3H4O
3-nonanone C9H18O
Carboxylic Acid
• Hydrocarbons with a –COOH group attached
• To name it give it the suffix “–oic acid”, the C
in the group does count
• Subtract one C one H and add COOH
• This group looks like…
R-C=O
O
H
Pentanoic acid
C4H9COOH
=O
O
H
Everything so far…
• Alkanes, alkenes, and alkynes
• Isomers, halogenated and cyclic
-OH
*R means any carbon chain
Alcohols
Carboxylic Acids
R-OH
R-C=O
-ol
-oic acid
-al
Ketones
R-C-R
=O
Aldehydes
on the end
R=O
-one
Predicting organic reactions
• Addition reactions occur by adding
halogens or hydrogen to alkene or alkynes.
• In the reaction, the new molecule takes the
place of the double or triple bond.
• Cl2 + CH3-CH=CH2  CH3-CClH- CClH2
example
• 1- butene is reacted with fluorine
• C4 H8 + F2  C4H8F2
Predicting organic reactions
• Substitution reactions occur by adding
halogens to an alkane.
• In the reaction, the new molecule takes the
place of a hydrogen.
• Cl2 + CH3-CH3  CH3-CClH2 + HCl
• Cl2 + C2H6  C2ClH5 + HCl
Predicting organic reactions
• Combustion reactions occur when an
organic compound is burned in oxygen.
• The products of a complete combustion
are water vapor and carbon dioxide.
• C6H12O6 + 6 O2  6 H2O+ 6 CO2
Predicting organic reactions
• Esterification reactions
• Made by reacting carboxylic acids with
alcohols.
Carboxylic acid
+
H-O-R
R-C-O-R
alcohol
O=
O=
R-C-O-H
Ester
+ H-O-H
Examples
• Fluorine is added to 1 propene
• Ethanol is burned in oxygen
• Chlorine is added to propane
• Ethanoic acid is reacted with 1-butanol
What is petroleum?
• Also known as crude oil
• It is a thick black sludge
• It comes from ancient plant and animal life
long since buried and kept under extreme
pressure for millions of years.
• It is composed of countless different organic
compounds.
What is made from petroleum
• Gasoline, kerosene, and rocket fuel
• Most plastics and other polymers
(elastomers and fibers)
• Synthetic rubbers and fabrics
• Most pharmaceutical drugs
• And several other things
• If we run out of petroleum it would have a
devastating effect on us
One compound that comes
from petroleum
Benzene
Which has the resonance structure
It also is drawn
as
Compounds that contain benzene are
called aromatic
• Aspirin (acetyl salicylic acid)
O-H
O
O=
O
Compounds that contain benzene are
called aromatic
• Trinitro Toluene (TNT)
- NO2
O2N-
O2N-
A few other aromatics
• Vinyl, napthalene (found in moth balls),
acetaminophen, penacillin
• Benzene is an extremely common organic
compound
• The fact that the double bonds flip back and
forth (called resonance) give it a very stable
structure
Polymerization
Esters
O=
• Esters- a functional group in the middle of a
carbon chain; R-COO-R
• It gets the suffix –oate
It is very similar to carboxylic acids
~In fact, it is formed by a
carboxylic acid and an alcohol
R-C-O-R
+ H-O-R
R-C-O-R
the water came
from…
O=
O=
R-C-O-H
+ H-O-H
Now if you have a few
compounds that have both a
O=
+ H-O-H
H-O-R-C-O- R-C-O-H
O=
O=
O=
Carboxylic acid end
+an alcohol end
H-O-R-C-O-H H-O-R-C-O-H
+
They could form an ester that looks like…
But the compound still has a…
And an alcohol end
Carboxylic acid end
So it could repeat this process thousands even
millions of times and make a whole bunch of…
poly esters
Of course, the scientific prefix for “whole bunch of” is
This is the basis for a polymer
• Polymer-A large chain-like molecule composed
of smaller molecules linked together
• The smaller units it is made up of are called
monomers
• monomers need to have ends that can join
together (or stack on top of one another)
• Like an extension cord or markers
• So you could (infinitely) join them together to
make a large polymer
Polymers can get very large
• common polymers have a molecular mass
of around 50,000 g/mol
• The first molecules seen under a
microscope were polymer chains
• Common polymers include things like…
• Nylon, Kevlar©, latex, PVC, rubber, acrylic,
vinyl, Deoxyribonucleic acid (DNA) and
carbohydrates
Piece of DNA
Polymers are put into three
classes
Plastics
ElastomersPolymers that can
be
stretched to 10x
their
normal size and
return to their
original shape
Elastic
Fibers
Polymers that
cannot stretch
or be
reshaped
once formed
Nylon and
Acrylic
Polymers that can
stretch and flex
more than fibers
but less than
Elastomers
Polypropylene
polystyrene
and PVC
(polyvinyl chloride)