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Unit 1 – Organic Chemistry
What is Organic Chemistry?
As early as _________, chemists recognized a difference between “organic” and “inorganic” compounds.
In 1828, Frederich Wöhler discovered that ________ - an organic compound - could be made by heating ammonium cyanate (an inorganic compound).
Organic Chemistry came to mean the chemistry of compounds from ____________ things but we now know that this definition is too limited.
Study of compounds that contain _____________ – organic compounds.
These are compounds where ______________ is bonded to another C or to H and sometimes to O, N, S or P.
Exceptions are CO32-, CN- ,C2
2-, oxides of C.
Inorganic Compounds
Anything that doesn’t contain carbon except for complex ions that contain carbon, carbide ion and oxides of carbon.
Nature of Carbon
Half filled outer shell (4 v.e)
Can bond to ____ other atoms
Intermediate electronegativity
More likely to _________ than gain/lose electrons.
Isomers
Same number of atoms, different ___________
Two types:
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Constitutional Isomers or Structural isomers – different SEQUENCE of atoms.
Stereoisomers – same atoms and sequence but different _____ orientation.
Diastereomers – double bonds. There are “cis” and “trans” isomers. The
C atom must have 2 different groups.
______________________ – C bonded to 4 different groups. Mirror
image – NOT superimposable.
Hydrocarbons
Contain only carbon and ________________________
Classified by type of carbon-carbon bond (single, double or triple).
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_______________________ hydrocarbons are those whose carbon backbone forms a straight chain, branched chain(s), or a ring (cyclic) structure.
When a hydrocarbon chain is attached to a main chain, it is called an ___________________.
_______________________ hydrocarbons are unique ringed structures based on benzene. The bonds have properties intermediate between single and double bonds.
Textbook Reading – pages 8-13
Textbook Questions – page 14: #1-7, 12.
Hydrocarbons
Alkanes
Single bonds
Saturated (with_____)
CnH2n+2
Non-polar, insoluble, small- ______________, med-liquids, large – waxy solids.
Methane, ethane, propane, butane
Naming Rules
See Page 17 for further explanation of naming rules.
1. Find the longest continuous chain of carbons in the molecule and name it. This is the parent chain of the molecule. Be careful, the longest continuous chain is not always obvious because it may zigzag. (HINT! highlight the parent chain in some way.)
2. Number the carbons in the parent chain. Designate the carbon at the end to which branching is closest as number 1.
3. List the alkyl groups present.
4. If there is more than one type of alkyl group in the molecule you can list their names in alphabetical order.
5. If an alkyl group occurs more than once, use a Latin prefix to indicate the number present. The Latin prefixes are di = 2, tri = 3, tetra = 4, pent = 5, and so on. - e.g. two methyl groups would be represented as dimethyl
6. Use a number to indicate the location of each alkyl group on the parent chain.
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7. Use proper punctuation: commas are used to separate numbers, and hyphens are used to separate numbers and letters.
Alkyl Branches
1) Use prefix for branch based on number of carbons in chain + yl (methyl, ethyl, etc.)
2) Write the number of the location (point of attachment) of the branch using the lowest possible numbers.
3) Numerals separated by commas, numerals and letters separated by hyphens, branches and parent chains are not separated.
Naming Reference Table
Name and draw the following continuous-chain hydrocarbons:
1. C6H14
2. C10H22
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Another common way to represent a ____________________ is to use a condensed structural formula. For example, the chemical formula of C4H10 can be represented as:
3. Write the name of the following:
4.
5. Draw the structural formula for the following:
2,3-diethyl-4,5-dimethylhexane
Online Practice: http:// www.docbrown.info/page06/DFalkanes/DFalkaneQmc.htm
Textbook Reading: Pages 15-21
Textbooks Questions: Page 19: #1-11
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Alkenes and Alkynes
Alkenes
Double _____________
Unsaturated (not the maximum # of H bonded)
CnH2n
Non-polar, _________________, location of double bond affects bp.
Naming
Similar to alkanes but number Carbon so that the carbons involved in double bond get lowest number.
The number of the first carbon involved in the double bond becomes a part of the suffix. i.e: “-2-ene”
Examples –Name them!:
Reading – Page 22-26
Practice – Page 26, #23-34
Extra Practice – page 27, #35-44
Alkynes
_______________ bond
unsaturated
CnH2n-2
Example: acetylene (fuel used in welding)
Non-polar, insoluble, higher bp than corresponding alkanes.
Naming
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Similar to alkenes except ______________ contains position of triple bond and “yne” i.e. “-3-yne”
Name it!
Reading – page 28-30
Practice – Page 30, #45-54
Cyclic Aliphatics and Aromatics
Cyclic Aromatics
• Hydrocarbon chains that form _______________
• A ring of three or more carbons connected by single bonds is called a _____________ alkane or a cycloalkane.
• Cyclic alkanes have ________ less hydrogen atoms than their corresponding continuous-chain alkanes.
• The general formula for a cyclic alkane is CnH2n which is the same as the general formula for an alkene that has one double bond.
• Cyclic alkenes are rings that possess a double carbon to carbon bond. They are sometimes referred to as __________________.
• All insoluble except for cyclopropane.
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• Add the prefix “cyclo” to the alkane name.
• Reading: Page 31-35
• Problems: Page 34 - #55-64
Aromatic Hydrocarbons
• Contains a ____________ ring
• Very stable, liquid at room temp, strong odours.
• Bonds are intermediate between double and single bonds due to delocalized electrons – ___________________________________
• Benzene is the root if side groups have 6 or fewer carbons.
• If the benzene ring is attached to a chain with 7 or more carbons, the ring is a side group and is referred to as a “________________” group.
• Use same rules as with other hydrocarbons.
___________________________
____________________________________
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• Reading: Page 35-39
• Problems: Page 38: #65-74
Hydrocarbon Derivatives
Compound consisting of a hydrocarbon with one or more functional groups attached.
Alcohols
Defined by the functional group called _________________ (-OH).
The general formula for an alcohol is R-OH where R represents an alkyl group.
Physical Properties
Small – ______________
Larger – non-polar
Higher bp than corresponding alkanes
Alcohols with fewer than 12 carbons are liquids at r.t.
Toxic!
Naming
End in –ol
Count to find the number of carbon atoms in the longest continuous chain (the alkyl stem).
Name the continuous chain of carbons in the same way you would name a corresponding alkane.
Change the -e ending of the alkane name to -ol.
Indicate the location(s) of the hydroxyl group(s) using the lowest possible number. Insert the number(s) into the suffix “butan-2-ol or pentane-2,3-diol”.
If the alkyl group is branched, priority in the numbering of the parent goes to the location of the hydroxyl group.
Write the IUPAC names that correspond to these structural formulas.
The longest chain is four carbons long, so the structure is derived from butane. The location of the hydroxyl group has to be assigned the lowest possible number - in
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this case the hydroxyl group is located on carbon #1. The name of the compound is ________________________________.
The longest chain is four carbons long, so the structure is derived from butane. There is a hydroxyl group located on carbon #2 (lowest possible number), so the name of the compound is _____________.
____________________________________
_____________________________________________
Priority for numbering goes to the location of the hydroxyl group. Alkyl groups have secondary importance in the naming scheme.
Draw a structural formula for each alcohol.
a. 2-propanol
First you draw the structure that corresponds to the alkyl prefix prop.
Then, based on the number in the name 2-propanol, you add the hydroxyl group to carbon #2.
b. 3-pentanol
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c. 2-methyl-2-butanol
Alcohols: Two Special CasesCompounds that possess more than one hydroxyl group are called polyalcohols. Example: enthane-1,2-diolThe suffixes –diol and –triol are added to the name to indicate two and three –OH groups.
Decompose the name from right to left.
diol means two hydroxyl groups
ethane means two single bonded carbon atoms
1,2 means the hydroxyl groups are located at carbons 1 and 2
Reading: Page 42-46 Problems: Page 34: #75-84
Haloalkanes
a compound that contains one or more ______________ atoms as part of its molecular structure.
many important uses including: fire retardation anaesthesia plastics manufacturing refrigeration/cooling systems
Physical Properties
Small – slightly soluble, most are insoluble Higher bp than corresponding __________________.
Naming
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The Halogen names are shortened and –oro is used as an ending. Eg. Fluoro, chloro, bromo, etc.
Identify and name the longest continuous chain of carbon atoms. Identify and name the halogen substituent(s). Assign lowest possible numbers to the
substituents. (If there are alkyl groups, these have priority in numbering) List the substituents in alphabetical order using appropriate prefixes. Write the full name of the compound beginning with the names of the substituents and
ending with the name of the parent.
Examples
The parent is propane. It has chlorine substituents at carbons #1 and #3. The name of the structure is_____________________.
The parent is ethane. In alphabetical order, the substituents are two chlorine atoms at carbon #1 and two fluorine atoms at carbon #2. The name is _______________________
___________________________________
Write a structural formula for 1-chloro-1,2-difluoroethane.
Reading: Pages 46-49 Problems: Page 49: #85-95
Aldehydes
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Contain a terminal carbonyl group (-C=O). This means the carbonyl is at the ____________ of the molecule.
Physical Properties
Bp lower than corresponding _______________ Most are liquids at r.t. Those with greater than 14 Carbons are waxy _________________. Small=soluble, greater than 7 C = insoluble.
Naming
Identify the longest continuous chain of carbon atoms (including the carbon atom in the carbonyl group). Note that the carbonyl carbon is designated as carbon #1 - this is a very important point!
Write the name of the corresponding alkane and replace the -e ending of the alkane name with -al.
Note that the carbon of the carbonyl group is counted as part of the carbon chain for naming purposes. AND there can be alkyl groups.
Examples:
_________________
___________________________
___________________________
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__________________________________
Reading: Pages 50-53 Practice: Page 52 - #96-105
Ketones
also contain the functional group called ____________________ unlike the aldehydes, the carbonyl group in ketones is located on a ________________ carbon. general formula for ketones is R–CO–R'.
Physical Properties
Similar bp to _______________________ Smaller than 15 C are liquids, larger are waxy solids.
Naming
1. Identify the longest continuous chain of carbon atoms (including the carbon atom in the carbonyl group).
2. Write the name of the corresponding alkane and replace the -e ending of the alkane name with -one.
3. If the carbon chain is five carbon atoms or longer, indicate the position of the carbonyl group by assigning it the lowest number possible.
Examples
____________________________
_______________________________
_____________________________________
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_________________________________________
Reading: Pages 53-57 Problems: Page 56: #106-115
Carboxylic Acids
Organic acids are common. The one you are probably the most familiar with is ethanoic acid which is also known as acetic acid or simply vinegar and fatty acids
Carboxylic Acids
The functional group that gives organic acids, also known as carboxylic acids, their chemical and physical properties is the __________________ group, -COOH.
You can think of a carboxyl group as a carbonyl group and a hydroxyl group rolled into one.
+ =
The general formula for the carboxylic acids is RCOOH where R represents a __________________ atom or alkyl group.
Unlike carbonyl and hydroxyl groups, carboxyl groups are always terminal. The carbon atom of the carboxyl group is considered to be part of the alkyl stem.
Naming Carboxylic Acids
To name a carboxylic acid when given a structural formula:
1. name the longest continuous chain of carbons, including the carbon of the carboxyl group, using an alkane name. The carbon atom in the carboxyl group is carbon #1.
2. if present, list the names of any alkyl branches and assign each a number. Build the name as you would for a branched hydrocarbon.
3. replace the -e ending of the hydrocarbon name with the suffix -oic.
4. add the word acid to the first name to make a phrase.
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Example
a. _______________________________
b. _______________________________
________________________________________
______________________________________
Reading: Pages 57-61 Practice: Page 61 - #116-125
Esters
Esters are abundant in nature. Many of the pleasant odours you associate with flowers and berries are due to esters as are the scents of bath oils, shampoos, soaps, and room fresheners, etc.
If you see "artificially flavoured" on the packaging of your favourite snack or candy, chances are that the flavour is due to a synthesized ester.
The functional group of an ester is actually a combination of a _____________ group from an organic acid and an ether link from an alcohol.
Esters are produced by reacting carboxylic acids with ___________________________.
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The general formula of an ester is RCOOR' where R represents hydrogen or a carbon chain/alkyl group and R' represents an alkyl group.
Naming Esters
1. count to find the number of carbon atoms in the -OR' component of the structural formula (the part derived from an alcohol) and assign it an alkyl group name.
2. count the number of carbon atoms in the R-C=O component of the structural formula (the part derived from the carboxylic acid) and assign it an alkane name with an -oate ending in place of the -oic ending.
3. combine the names to make a phrase.
Example
a. The -OR component of the molecule is propyl. The R-C=O component is derived from propanoic acid so its name is propanoate. The two names are combined to give _________________________________.
b. _____________________________________.
________________________________________
________________________________________
Reading: Pages 61-65 Practice: Page 65: #126-135
Ethers
Used as the first ___________________________ for surgery
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Oxygen atom single bonded to 2 carbons. R-O-R’ = alkoxy group
Physical Properties
Flammable Slightly __________________ 2-3 carbon – gas, larger - liquid
Naming
count to find the number of carbon atoms in the R group of the structural formula (the part bonded to the O) and assign it an alkane name. This is the root.
count the number of carbon atoms in the R’ component of the structural formula (the alkoxy group) and assign it an alkane name with an -oxy ending in place of the -ane ending. Indicate the location on the main chain with a number. This is the first part of the prefix.
Identify any side chains and include them as the 2nd part of the prefix. combine all three to name the compound.
1. Name these ethers :
a. ___________________________
b. ___________________________
c. ___________________________
Reading: Pages 66-70
Practice: Page 69: #136-146
Amines
You might recall that esters tend to have pleasant scents. Well, the same cannot be said for amines and amides. Their scents are characteristically unpleasant. ___________ is one of many common examples.
Amines are derived from ammonia (NH3)
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The functional group is one hydrocarbon group bonded to an _______________ group (-NH2). These amines have the general formula RNH2 where R represents an alkyl group.
To name an amine, identify the alkyl group and add the suffix -amine to its name.
Example
______________________________
_______________________________
Reading: pages 70-74
Practice: Page 74: #147-158
Amides
The functional group of an ____________ consists of a carbonyl group and an amino group.
An amide can be produced by reacting a carboxylic acid with ____________ (NH3).
The general formula RCONH2 where R represents hydrogen or an alkyl group.
To name an amide, write the name for the carbon chain containing the carbonyl group, drop the -e ending, and add the suffix -amide.
Note: Unlike Amines, we do not name the carbons as alkyl groups, but as alkanes.
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Example
__________________________
__________________________________
Reading: Pages 75-80 Practice: Page 79: #159-169
Summary of Polarity
Amide>acid>alcohol>ketone=aldehyde>amine>ester>ether>alkane
Priority of Functional Groups in Naming = Appendix B (page 730).
Organic Reactions
Addition
• Involves alkenes and ___________________• Atoms are added to the double or triple bond• Reactant is often water, hydrogen or halogen.• To understand which product will form when isomers are possible, use Markovnikov’s Rule: H
will attach to the C already bonded to the most H atoms.
• Reading: Pages 96-99• Practice: Page 99: #1-6
Elimination
• Atoms are removed and ____________________ bonds formed• Reverse of addition• Eg. Alcohol à alkene + Y-Z (in presence of strong acid)• Eg. Haloalkane à alkene (in presence of strong base)
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• Reading: Pages 100-102
• Practice: Page 102: #12-16
Substitution
• H or functional group replaced by another
• Mainly alcohols and ___________________ involved
• Alcohol + acid à haloalkane + water
• Haloalkane + OH- à alcohol + anion
• CH3-CH2-OH + HCl à CH3-CH2-Cl + H-OH
• Ethanol + hydrogen chloride à chloroethane + water
• Reading: Pages 103-104
• Practice: Page 104: #24,26-28, 31
Condensation
• 2 large molecules react to form a larger molecule + ________________
• Carboxylic acid + amine à amide + water
Esterification
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• Special type of _______________________
• Carboxylic acid + alcohol à ester + water
Hydrolysis
• Reverse of ________________________
• Water is used to break bonds
• Reading: Pages 105-108
• Practice: Page 108: #33-42
Oxidation and Reduction
• Oxidation: carbon forms __________ bonds to Oxygen and fewer to Hydrogen.
• Eg. Alcohol à aldehyde or ketone OR aldehyde à carboxylic acid
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• Reduction: carbon forms _________________ bonds to Oxygen and more bonds to Hydrogen.
• Eg. Aldehyde or ketone à alcohol OR alkene à alkane
• Reading: Pages 109-110
• Practice: Page 113: #43-48
Polymer Equations
• Polymer: a large molecule made up of repeating ________________ (monomers)
• Eg. Proteins, carbohydrates, plastics, chewing gum.
• Addition Polymerization
– Alkene monomers joined to form a polymer
– Named for the monomer
– Eg. Polystyrene, polyacylamide, polyethene.
• Condensation polymerization
– Monomers joined through condensation
– Water is usually formed
– Each monomer has 2 functional groups
– Joined by a ester or amide linkage
• Reading: Pages 116-126
• Practice: Page 121: #53-58