ORGANIC CHEMISTRY

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ORGANIC CHEMISTRY
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ORGANIC MOLECULES
General information - Organic chemistry refers to
the chemistry of CARBON compounds - The carbon
atom can form a maximum of 4 covalent bonds - It
can bond to other carbon atoms, to form single,
double or triple bonds - Can bond to other carbon
atoms to form long chains, branches or ring
structures - Can bond with other atoms (eg.
Hydrogen, oxygen. Nitrogen, halogens, etc.)
Functional groups - Organic molecules can be
separated into families according to their
chemical and physical properties - The
structural property that enables us to classify
the compound according to its reactivity is
known as the FUNCTIONAL GROUP - The functional
group is an atom or group of atoms that are
characteristic of a group of compounds that
form a homologous series and are responsible for
the specific property of that group
Homologous series - Organic molecules
corresponding to the same family form a
homologous series - Compounds in a homologous
series have the same functional group and can be
described using the same general formula. (Eg.
Alkanes CnH2n2)
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Representing organic molecules - Different types
of formula can be used to represent organic
molecules - Molecular formula (indicates the
amount of atoms in the molecule) C4H10
(Butane) - Condensed structural formula
(shows how the atoms are bonded but no bonds)
CH3CH2CH2CH3 (Butane) - Structural
formula (Shows all atoms including their
associated bonds)

• Line structure (lines represent bonds, ends of
  lines represent carbon atoms)

• Three dimensional formula (wedges to indicate
  bonds into and out of page)

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Classification of organic compounds
Isomers - Molecules that have the same molecular
formula, but different structures - Only
consider structural isomers (though you get
geometric and stereo isomers) - Example C4H10
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• Alkanes
• Saturated hydrocarbons (only contain single
  bonded carbon atoms)
• Homologous series Cn H2n2
• Naming Alkanes
• IUPAC system of naming
• Involves the use of a prefix, root and suffix

• PREFIX Explains where, and which functional
  groups are present
• ROOT Number of carbon atoms
• SUFFIX Family or homologous series

- The following are used to indicate the number
of carbons present in the molecule
Number of Carbons Root name
1 Meth -
2 Eth -
3 Prop -
4 But -
5 Pent -
6 Hex -
7 Hept -
8 Oct -
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• Some molecules contain branches (where a
  hydrogen has been replaced with carbon
• chains) The carbon chain is called an ALKYL
  group
• These are represented with an R- in the
  structural formula
• These alkyl groups are named as follows

Alkyl group Name
CH3- Methyl -
CH2CH3- Ethyl -
CH2CH2CH3- Propyl -
CH2CH2CH2CH3- Butyl -
Procedure for naming 1) Find the LONGEST
continuous carbon chain in the molecule (becomes
root) 2) Identify the attached alkyl groups 3) To
indicate the positions of the branches, number
the carbon atoms in the longest chain,
starting from the side closest to a branch! 4) To
write down the name, start by writing down the
position and name of all the attached groups
in alphabetical order. (if there is more than 1
of a particular alkyl group, use the
prefixes Mono, di, tri and tetra to indicate the
number of groups Note the name is written as 1
WORD, with numbers and words separated by dashes
(-)
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• Cycloalkanes
• - Carbon atoms can bond to each other to form
  rings (consider cyclohexane C6H12)

• Homologous series Cn H2n
• Naming Cycloalkanes
• If substituents are present, the Carbon atoms in
  the ring are numbered in such a way
• that the substituent is on the lowest number
• 2) Arrange the substituents in alphabetical order
  and use di, tri and tetra to indicate the
• number of like substituents
• 3) If the ring contains 2 different alkyl groups,
  number the C atoms in the ring so that
• the alkyl group that is first in the alphabet
  receives the lowest number

Note - Alkanes are our most import fuels
(fossil fuels) - Combustion of alkanes
(oxidation) is HIGHLY EXOTHERMIC and produces
carbon dioxide and water as products
(along with energy) ALKANE
O2 ? H2O O2 ENERGY!!!
?H lt 0
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Structural and physical properties of alkanes 1)
Phases (at room temperature) - C1 to C4
alkanes gases - C5 to C17 alkanes liquids
- C18 solids (plastic PET) -
The intermolecular forces between alkane
molecules increases as the molecule
increases in size (increased molecular mass)
2) Densities - less dense than water
- density inceases as size increases (also
explained by intermolecular forces) 3)
Volatility and vapour pressure -
volatility is the measure at which a liquid
changes to a vapour - Alkane volatility
decreases as size increases (stronger forces,
less volatile) - Vapour pressure refers to
the pressure caused by the vapour formed -
Thus less volatility, less vapour pressure 4)
Viscosity - viscosity is refers to the
degree of fluidity (or flow) of a liquid -
Viscosity increases with intermolecular force
strength
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5) Solubility - The ability to dissolve in
another substance (solvent) - Alkanes are
non-polar, thus they will dissolve in non-polar
solvents (organic solvents and not in a
polar solvent such as water 6) Melting and
boiling points - Consider the table of
melting and boiling points - van der waals
forces (intermolecular forces) increases as the
molecule size increases. The stronger the
forces, the more energy is required to break the
forces, resulting in a higher boiling point
- Similarily with melting points, as the
size of the molecule increases so does the
melting point - It can be seen in the graph
that the increase is not smooth (as is the case
with boiling). This is because alkanes
with an even number of carbon atoms pack
together very well in the solid phase, and thus
more energy is required to overcome the
intermolecular forces
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• Alkenes
• Unsaturated hydrocarbons (covalent double bonds
  between carbon atoms)
• The double bond is a centre of high reactivity
  (high electron density)
• Homologous series Cn H2n
• The simplest alkene is ethene

• Procedure for naming
• Find the longest chain containing the double
  bond. (This becomes the root)
• Add the suffix ene to the root
• Number the chain starting from the end closest
  to the double bond
• The position of the double bond is indicated by
  the number on the first carbon atom
• of the double bond
• 5) When the root chain contains branched
  substituents, the same rules used for naming
• alkanes is followed
• Note The position of the double bond can be
  indicated in two ways

3,3 dimethyl 1 butene OR 3,3
dimethylbut 1 ene
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• Cycloalkenes
• - The number of carbon atoms in the ring
  determines the root
• - Number the ring in such a way so that the
  double bond is between C1 and C2
• - As well as allowing for the lowest numbers on
  the substituents
• - If there is only one double bond present, The
  carbon on which it starts doesnt have
• to be indicated in the name (as it will always
  start on C1)
• - If there are 2 double bonds, the molecule is
  known as a DIENE
• In this situation, the suffix diene is used,
  and the position of the double bonds
• must be indicated
• - When there are two sets of double bonds
  connected to a single carbon atom, the
• molecule is known as a CUMULATED DIENE

Note Consider the following molecule

• This is an example of a compound with CONJUGATED
  double bonds
• A conjugated double bonds system is a system
  where single and double bonds follow
• one another in a carbon chain
• These are very interesting molecules when it
  comes to reactivity because the electrons
• in the double bonds are DELOCALISED over the
  whole molecule!

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Structural and physical properties of alkenes
Phases (at room temperature) - C2 to C4 gases
- C5 to C15 liquids - C16 solids
(plastic PET) Alkenes are NON POLAR -
Thus weak van der waals forces exist between
molecules - alkenes insoluble in water
(polar) - Soluble in organic solvents
(non-polar) Melting and boiling points -
Consider the table of melting and boiling points
- These can be explained by the van der waals
forces - strength of forces increases as the
molecule size increases
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Alkynes - Unsaturated hydrocarbons (covalent
TRIPLE bonds between carbon atoms) - The triple
bond is a centre of high reactivity (high
electron density) - Homologous series
CnH2n-2 Procedure for naming The same rules
apply as for the naming of alkenes, but the
suffix yne is used Structural and physical
properties of alkynes - The phase of the alkynes
also depends on the molecular mass (size) of the
molecule Phases (at room temperature) - C2 to
C4 gases - C5 to C17 liquids - C18 solids
(plastic PET) Alkynes are NON POLAR - Thus
weak van der waals forces exist between
molecules - alkynes are insoluble in water
(polar), but Soluble in organic solvents
(non-polar) - Alkynes are less dense than
water Melting and boiling points - Can be
explained by the van der waals forces -
strength of forces increases as the molecule size
increases
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Structural and physical properties of alkynes -
Consider the two types of van der waals forces
- Van der waals dispersion (or London) forces
- When 2 NON-polar molecules approach each
other, attraction as well as repulsion,
between the nuclei can cause an unequal
distribution of charge - This causes,
TEMPORARY dipoles to be produced - These
temporary dipoles induce temporary dipoles in
adjacent molecules - This results in a weak
force of attraction between molecules - Van
der waals dipole-dipole forces - When atoms
of different electronegativities bond with each
other to form a molecule, the molecule
that is formed has an unequal distribution of
charge - This unsymmetrical charge
distribution results in the formation of a POLAR
molecule (dipoles one side slightly
negative, the other slightly positive) -
When polar molecules are close together they
exert forces on each other
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Alkyl halides - Alkane where one of the hydrogen
atoms has been replaced with a halogen - R-X,
where X F, Cl, I, Br Homologous series
CnH2n1X Procedure for naming - Determine
length of longest chain (root name) - Start
numbering from side closest to the first
substituent (regardless of what it is) - If more
than one type of halogen present, indicate the
number using di, tri or tetra - If there are two
different types of halogens in the molecule, each
one present must receive its own number and
be arranged in alphabetical order - Should the
numbering of the root chain, from both sides,
give the same smallest number, alphabetical
preference is given to the one side
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Structural and physical properties of alkyl
halides
1) Alkyl halides have higher melting points and
boiling points than alkanes with the same
number of carbon atoms - with alkane
molecules, there are only London forces involved
- with alkyl halides there are
dipole-dipole forces involved too - the
dipole-dipole forces are stronger and thus more
energy is needed to separate the
molecules 2) Melting points and boiling points
of alkyl halides increases as the number of
carbon atoms increases in the molecule -
As before, the greater the molecular mass of the
molecules, the stronger the forces
involved 3) Melting points and boiling points
of alkyl halides increases as the size of the
halogen atom increases (F lt Cl lt Br) - The
larger the group, the more surface area 4)
Melting points and boiling points of alkyl
halides decreases with an increase in the
number of branches and unsaturated bonds -
moving the halogen atom closer to the centre of
the chain causes the molecule to become
more circular and thus reduces the surface area
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Reactions of organic molecules
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Combustion (oxidation)

• Reaction of alkanes with oxygen
• Forms H2O and CO2 or CO
• In the presence of sufficient oxygen
• In the absence of sufficient oxygen
• Consider n 1, 2, 3, 4

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Substitution (halogenation)

• Alkanes react with halogens (F2, Cl2, Br2) when
  heated or in the presence of light
• Heated indicated with D and light indicated hf
• hf
• D
• Examples methane reacting with chlorine
• ethane reacting with bromine
• pentane reacting with flourine
• Substitution in alkanes occurs when one or more
  hydrogen atoms in an alkane molecule are
  substituted by another atom or group of atoms.
  Energy in the form of sunlight or heat is
  necessary for the reaction to occur
• Note - The product that is formed is known as
  an alkyl halide or haloalkane
• - The reaction is often difficult to
  control, and further substitution can
• occur, replacing all the
  hydrogen atoms with halogen atoms

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Elimination

• Elimination reactions involve the removal of a
  smaller molecule out of a larger molecule
• An important example of the this type of reaction
  is CRACKING
• This involves the division of a larger
  hydrocarbon chain into smaller chains
• Pt
• 800OC
• Depending on the length of the chain, multiple
  cracking sequences can occur
• Consider the cracking of butane (3 possible
  products)
• Not all products will produce the same yield

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Addition reactions of the alkenes

• An addition reaction is a chemical reaction where
  a molecule attaches to a double or triple bond of
  a second molecule to form a single molecule.
  During the reaction the multiple bond is broken
  and new atoms are added to the molecule to form a
  more saturated product
• Examples of addition reactions
• 1) Hydrogenation (adding two hydrogen atoms)
• - The catalyst (Pt, Ni, Pd) lowers the
  activation energy of the reaction by providing an
  area where the reactants can come into closer
  contact with one another
• 2) Halogenation (adding two halogen atoms)
• Note The halogenation reaction where Br2 is
  added is the test for unsaturated hydrocarbons
• - A solution containing a saturated
  hydrocarbon will discolour with the addition of
  bromine water

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• 3) Hydrohalogenation (addition of hydrogen
  halides to alkenes)
• Note Markovnikovs rule
• - When a polar molecule (eg. H-F, H-Cl, H-Br,
  H-I, H-OH) is added to a hydrocarbon
• double bond, the hydrogen atom is added
  to the carbon atom with the most H- atoms
• while the negative part of the molecule
  (F, Cl, Br, etc) is added to the carbon
• atom with the most alkyl substituents

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• Hydration (addition of water to alkenes)
• - In the presence of a catalyst (H2SO4),
  water is added to an alkene to form an alcohol
• - One of the hydrogen atoms in the water
  molecule (H-OH) will bond to the carbon atom of
  the double bond (obeying the Markovnikov rule)
  
• Examples - hydration of 2-methylpropene
• - hydration of 1-methyl-1-cyclohexene

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Addition reactions of the alkynes

• Just like alkenes, alkynes can also undergo
  addition reactions (result of unsaturated nature)
• 1) Hydrogenation (addition of hydrogen)
• - 2 possible products
• - The reaction can be stopped at the
  intermediate product (alkene)
• - Or it can convert the alkyne all the way to
  the saturated alkane

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(2) Halogenation (addition of halogens) - 2
step process - The solution changes from
orange-brown to colourless
(3) Hydrohalogenation (addition of halogen and
hydrogen) - 2 step process - The
markovnikov rule applies
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• Substitution reactions with alkyl halides

• Alkyl halides are easily converted to other
  functional groups
• The halogen atom, together with its bonding
  electron pair (halogens more electron negative
  than carbon) can leave the alkyl molecule to form
  a stable halide ion
• We say that the halide is a good LEAVING GROUP
• Note Nu- is a Nucleophile (nucleus loving
  species)
• Reaction with potassium/sodium hydroxide (alcohol
  formation)
• - Alkyl halides dont mix with water, so
  before treating them with the strong base (KOH or
  NaOH), they must be mixed in ethanol

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• Reaction with water - hydrolysis (alcohol
  formation)
• - Alkyl halides dont mix with water,
  therefore they must be mixed in ethanol
• Reaction with ammonia (amine formation)
• - Alkyl halides dont mix with water,
  therefore they must be mixed in ethanol
• - This reaction takes place under high
  pressure conditions

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Elimination reactions with alkyl halides

• During an elimination reaction of alkyl halides,
  the halogen atom and the hydrogen atom of the
  adjacent carbon atom are removed from the
  molecule
• Reaction with potassium/sodium hydroxide (alkene
  formation)
• - This reaction is known as a
  Dehydrohalogenation reaction
• - It can only occur if the alkyl halide is
  heated in the presence of the strong base
• Note Some alkyl halides (more than 3 carbon
  atoms) can produce 2 different alkenes as
  products of elimination

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• Note One product is more favoured than the other
  (follows Zeitzevs rule)
• If more than one product is possible during
  elimination, the main product
• will be the alkene with the highest substituted
  double bond
• Note Substitution and elimination reactions
  compete with each other under the conditions of
  strong base (KOH or NaOH) addition the preferred
  product formed depends on whether a PRIMARY,
  SECONDARY or TERTIARY halide is involved!
• Primary
  Secondary Tertiary
• Primary Halides - Substitution
• Secondary halides - Substitution / elimination
• Tertiary halides - Substitution / elimination

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• Aromatic hydrocarbons
• Aromatic compounds contain one or more benzene
  rings
• Benzene (C6H6) simplest aromatic hydrocarbon
• The electrons in the double bond in benzene are
  able to move around in the ring
• The electrons are delocalised
• Thus the double bonds are able to move around
  the ring
• Naming aromatic compounds
• All compounds based on a benzene ring have their
  names ending with benzene
• The naming of substituents work the same as in
  any other orgainc molecule
• Many single substituted rings have common names,
• Examples

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• Benzene doesnt undergo addition reactions (even
  though there is a high measure of unsaturation)
  as any addition reaction will result in the very
  stable conjugation of the double bonds being
  disrupted!
• It undergoes substitution reactions, where one of
  the hydrogen atoms are replaced with a different
  atom (example halogen atom)

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FUNCTIONAL GROUPS CONTAINING OXYGEN

• ALCOHOLS AND ETHERS
• Homologous series CnH2n1OH
• Shortened notation ROH
• Naming compounds containing alcohol groups
• - The name is derived from the alkane (longest
  chain) with the suffix -ol
• - The position of the OH group is indicated
  according to the regular numbering
• system used with molecules containing
  other functional groups
• - Compounds that contain more than 1 OH group
  are called (di, triols)
• Physical properties of alcohols
• - Alcohols have a polar OH group as well as a
  non-polar hydrocarbon part
• - Thus we have two types of bonding present
• 1) Hydrogen bonding (between OH groups)
• 2) Van der Waals forces (between alkyl
  groups)

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• But is an alcohol molecule polar or non-polar?
• It depends on the size of the non-polar alkyl
  group!
• The larger the alkyl group gets, the more
  significant it becomes in the molecule and thus
  the compound becomes less soluble in water (ie
  more non-polar)
• Rule When there are 4/more carbon atoms in the
  dominant part of the molecule, the molecule is
  considered non-polar (thus insoluble in water)
• But alcohols with branched alkyl groups are more
  soluble in water than those without branches!
  Because the branch decreases the contact surface
  of the non-polar part of the molecule!
• Boiling and melting points
• - Consider the table of boiling points on page
  76
• - The presence of strong hydrogen bonding
  between alcohol molecules
• increases the boiling points of alcohols
  (compared to alkanes van der waals
• forces)
• - It can also be seen that the boiling points of
  the alcohols increases as the
• number of carbon atoms in the molecule
  increases this is due to van der
• waals forces

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• Chemical properties of alcohols
• - Alcohols are prepared by the ADDITION of
  WATER to an ALKENE (hydration)
• or through SUBSTITUTION of a HALOGEN
  (hydrolysis)
• - The following reactions are important to
  know
• Oxidation of alcohols
• - Note When Primary, secondary and tertiary
  alcohols undergo oxidation
• reactions, they form different
  products (functional groups)
• - Oxidation of PRIMARY alcohols
• - Acidified potassium dichromate (K2Cr2O7) or
  potassium permanganate (KMnO4)
• are excellent oxidizing agents
• - Primary alcohols react to form ALDEHYDES
  (R-CHO) and if heated further form
• CARBOXYLIC ACIDS (R-COOH)

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• Oxidation of SECONDARY alcohols
• - Secondary alcohols react to form KETONES
  (ROR) when heated in an acidified
• solution containing a powerful oxidizing
  agent
• - Tertiary alcohols do not react with acidified
  KMnO4 solutions (why not?)
• Substitution reactions of alcohols
• - Alcohols react with anhydrous halides (HI,
  HCl and HBr) to form alkyl halides
• - This substitution reaction is the reverse of
  the hydrolysis (forming alcohols)

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• Elimination of alcohols
• - Alcohols undergo the removal of water
  (dehydration) to form alkenes
• - When an alcohol is heated with sulfuric acid
  (H2SO4) or Phosphoric acid (H3PO4)
• as catalysts, the alcohol loses the OH
  group and an H atom from the adjacent
• carbon to form an alkene!
• - Question Can Methanol undergo elimination?!
• - Note Some alcohols can produce 2 different
  alkene products (Zaitsevs rule)
• Consider the summary of reactions on page 78
• ETHERS
• - Ethers are compounds that have an oxygen atom
  between 2 carbon atoms
• - General formula R O R
• - When studying ethers, it can be seen that
  they are similar to alcohols, except

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• Naming ethers
• - Ethers are named by giving the name of each
  alkyl group attached on either side
• of the oxygen atom, followed by the word
  ether
• - The alkyl groups are named in alphabetical
  order
• - Example consider the molecule R O R
  where
• Physical and chemical properties
• - The boiling points of ethers are much lower
  than those of the alcohols
• - The boiling points are quite similar to those
  of the corresponding alkanes with
• a similar molecular mass
• - Question What does this say about the forces
  between ether molecules?!

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• ALDEHYDES AND KETONES
• Aldehydes and ketones are compounds that have a
  CARBONYL group
• A carbonyl group is a group containing an
  oxygen atom
• that is bonded with a double bond to a carbon
  atom
• Aldehydes
• - contains a carbonyl group with at least
  one H-atom attached to it
• - the second group attached to the carbon
  can be another hydrogen (methanal)
• or it can be an alkyl group
• - Naming Aldehydes
• - aldehyde names end with al
• - The root name must contain the carbonyl
  group
• - numbering begins at the carbonyl group
• Ketones
• - Contains a carbonyl group that is bonded
  to two carbon atoms
• - Naming ketones
• - ketone names end with one

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• Physical properties
• - aldehyde and ketone molecules cannot form
  hydrogen bonds, so it is
• expected that their boiling points be
  lower compared to the corresponding
• alcohols
• - Aldehydes and ketones are polar molecules
  because of the polar carbonyl
• functional group. Therefore, van der Waals
  dipole-dipole forces can exist
• between molecules. These forces are the
  reason that aldehydes and ketones
• have higher boiling points than non-polar
  alkenes or less polar ethers
• 
  (consider table pg 92)
• - Aldehydes and ketones can form hydrogen bonds
  with water!
• - Thus they are soluble in water to a point. As
  with alcohols and ethers, the
• small molecules are soluble, but as the
  size of the alkyl group increases, the
• more Insoluble they become

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• CARBOXYLIC ACIDS
• A carboxylic acid contains a carboxylic group,
  -COOH (carboxyl carbonyl Hydroxide)
• General formula CnH2n1COOH
• Naming carboxylic acids
• - Carboxylic acids names end in -oic acids
• - The root chain must contain the carboxylic
  group (numbering begins here)
• - Number substituents according to position
  and arrange alphabetically
• Preparing carboxylic acids
• - Oxidation of an aldehyde (seen already)

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• Boiling points
• - Carboxylic acids have higher boiling
  points than ketones and aldehydes
• - Carboxylic acids have higher boiling points
  than alcohols even!
• - This is due to the fact that 2 hydrogen bonds
  form between 2 carboxylic acid
• molecules compared to the 1 between 2 alcohol
  molecules
• Solubility
• - Due to the polar nature of carboxylic acids,
  they are soluble in water
• - The solubility decreases as the size of the
  molecule increases
• - Molecules with
• - up to 4 carbons very soluble
• - up to 10 carbons slightly soluble
• - more than 10 insoluble
• Chemical properties

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• ESTERS
• Esters are derived from carboxylic acids
• They contain a carboxylic group of which the
  hydrogen atom (of the hydroxyl group) has been
  replaced by an alkyl group (R)
• Esterification (formation of esters)
• - When a carboxylic acid (RCOOH) and an alcohol
  (ROH) are heated in the
• presence of a catalyst (H2SO4) an ester
  (RCOOR) is formed! And water
• eliminated (H2O is obtained by removing OH
  and H from the reactants)

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• Naming Esters
• - Naming esters consists of two parts
• - The first part is derived from the root
  alcohol (ROH) and the second part is
• derived from the carboxylic acid (RCOOH)
• - The name has the suffix -oate
• Consider the following
• - Divide the ester between the C-atom of the
  carbonyl group and the O-atom
• bonded to the alkyl group

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• - When there are substituents present they get
  the number of the carbon
• atom to which they are bonded (numbering
  starts at C-atom closest to
• carbonyl group)
• - substituents on the alcohol part are the
  prefixes for the alcohol part of the
• name, while the substituents on the carboxyl
  part are the prefixes for the
• carboxyl part of the name!
• Boiling points
• - Dont form hydrogen bonds
• - Do form van der waals dipole-dipole forces
• - Thus have boiling points similar to aldehydes
  and ketones
• Solubility
• - Small esters soluble in water (dipole-dipole)
• - But larger ones insoluble

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• AMINES AND AMIDES
• AMINES
• - Amines are seen as alkyl derivatives from
  ammonia (NH3) where 1, 2 or 3 hydrogen atoms
• are displaced by alkyl groups
• - amines have the general formula RNH2
  (primary), R2NH (secondary) or R3N (Tertiary)
• - Amines can also be ARYL substituted
• - example phenylamine (aniline)
• - Naming amines (IUPAC)
• - General - Longest chain must contain
  the N-atom
• - Numbering starts from side closest to
  amine group
• - secondary amines
• - The other (shorter) alkyl group bonded
  to N-atom is named as an N-alkyl substituent
• - Tertiary amines
• - The other (shorter) alkyl group bonded
  to N-atom is named as an N, N-alkyl substituent
• - Physical properties
• - Amines are polar molecules

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• - It is not possible for tertiary amines
  to form hydrogen bonds as there are no more
• H-atoms bonded to the Nitrogen atom
• - Thus their boiling points are lower than
  the primary and secondary amines
• - Solubility
• - Smaller amines are soluble in water
  (because they can H-bond)
• - But Amines with more than 5 carbons
  have their H-bonding reduced and thus their
• solubility decreases!
• AMIDES
• - Amides are derivatives of carboxylic
  acids, they are formed by substituting the OH
• group with an amine group
• - COOH becomes CONH2
• - general formula RCONH2
• - Naming amines (IUPAC)
• - Amides are named as alkane amides
• - The suffix amide is used
• - An alkyl group attached to an N-atom gets
  N-alkyl at the beginning of the amide