Embed Size (px)
Citation preview
ORGANIC CHEMISTRY
Forms of Carbon
Carbon has four different allotropes.
Allotropes: Forms of the same element with different bonding patterns.
1. Diamond - Carbon is bonded to four other carbon atoms in a tetrahedral
pattern
2. Graphite - Carbon atoms are arranged in sheets or layers
3. Amorphous: -Not arranged in any predictable shape - Produced when carbon decomposes
4. Fullerenes - Globe-shaped, cage like arrangements of carbon atoms
ORANGIC COMPOUNDS
• A compound that is composed of carbon and hydrogen.
• It may also contain atoms of other elements, such as oxygen, nitrogen, sulfur, and chlorine.
Hydrocarbons: Basic organic compounds contain only carbon and hydrogen.
Substituted hydrocarbon:
Used when other elements are also present in addition to carbon and hydrogen.
Carbon atoms have the unique property of being able to bond to each other and form long "chains" of carbons, or to form circular "rings" of carbons.
The addition of one atom of a different element makes an entirely new compound is the reason that there are millions of organic compounds in the world.
The simplest hydrocarbon is methane, which is made of one carbon atom surrounded by four hydrogen atoms.
Aliphatic Hydrocarbons
Aliphatic hydrocarbons: The simplest hydrocarbons are those whose carbons are joined in line
one to another.
Alkanes 1. First group 2. Name of each of these compounds ends in "-ane" 3. They have the generic formula of CnH2n+2 4. They have a single covalent bond between them
Also called saturated hydrocarbons, which means that all of the carbons have the maximum number of bonds (4).
The first ten alkanes should be memorized, because their names are
the basis for most of the naming of the rest of the organic compounds.
1. CH4 : methane2. C2H6: ethane3. C3H8: propane4. C4H10: butane5. C5H12: pentane6. C6H14: hexane7. C7H16: heptane8. C8H18: octane9. C9H20: nonane10. C10H22: decane
Aliphatic Nomenclature
ALKANESALKANE NOMENCLATURE
1. Determine the longest continuous chain of carbon. (Parent chain)
2. Number carbons in parent chain. Do this by starting at the end that gives the attached groups the smallest number.
3. Add numbers to the names of the attached groups to identify their position. Numbers become prefixes to the name of the parent.
4. Use prefixes to indicate if more than one of the same attached group is present.
5. List attached groups in alphabetical order. Ignore prefixes.
6. Use commas to separate the numbers, hyphens to separate the numbers & words. The name of the alkane is written as one word.
Common Alkyl Groups
1. Methyl CH3
2. Ethyl CH2CH3
3. n-propyl CH2CH2CH3
Common Alkyl Groups
4. n-Butyl CH2CH2CH2CH3
5. Isopropyl CH3CHCH3
Common Alkyl Groups
6. t-ButylCH3
C CH3
CH3
Common Alkyl Groups
7. Amino NH2
8. Nitro NO2
9. Bromo Br
Common Alkyl Groups
10. sec-Butyl
CH3 C
CH2
CH3
H
Examples
A. CH3
CH3C CH2CH3
H
2-methylbutane
B. Br
CH3CH CHCH3
NO2
2-bromo-3-nitrobutaneC.
CH3
CH3
CH3
C CH2 CH
CH3
CH2 CH3
2,2,4-trimethylhexane
ALKENES
1. Next group of hydrocarbons 2. The carbon chain has a double covalent bond 3. They have the generic formula CnH2n 4. The names end in "-ene" 5. They represent the simplest of the unsaturated hydrocarbons. 6. An alkene has two less hydrogens than an alkane.
ALKENE NOMENCLATURE
1. Find the longest chain with the double bond.2. Number the chain so the double bond gets the lowest number.3. Name & number attached groups as you would for alkanes.4. Parent gets –ene ending; Indicate position of double bond with a
number.
ExamplesALKENE NOMENCLATURE
A.
CH2 CH CH2 CH3
1-butene
ALKENE NOMENCLATUREB.
CH3 CH CH CH3
2-butene
ALKENE NOMENCLATURE
C.
C C CC HH
H
H H
H
1,3-butadiene
ALKENE NOMENCLATURED.
CH2 C CH2
propadiene
ALKYNES
1. They have a triple covalent bond in the carbon chain 2. They have the generic formula CnH2n-2 3. They have two less hydrogens than alkenes
Alkyne Nomenclature
1. Find the longest chain with the triple bond & number it so the triple bond has the lowest number.
2. Name and number the attached groups. 3. Parent gets –yne ending; Indicate position of triple bond with a
number.
Examples:
Alkyne Nomenclature
A.
CH C CH2 CH3
1-butyneAlkyne NomenclatureB.
CH C CH3C
CH3
CH3
3,3-dimethyl-1-butyne
Cyclo-Compounds
1. Sometimes the chains can be circled and the end carbons join together.
2. This brings about the loss of two hydrogen atoms 3. An example is that of the six-carbon hexane forming the six-carbon
cyclohexane which has the formula C6H124. You use of the prefix "cyclo-" in front of the parent name, hexane
EXAMPLES
EXAMPLES
AROMATICS
1. The other main group of hydrocarbons is that of the aromatic hydrocarbons 2. They contain six carbons arranged in a "ring" and contain three
double covalent bonds between every other carbon-carbon pair. 3. The basic aromatic hydrocarbon is benzene, C6H6 4. Ways to represent benzene
Aromatics Nomenclature 1. Monosubstituted name like other hydrocarbons with –benzene as
the parent name.2. Disubstituted named using prefixes ortho (1,2) meta (1,3) para (1,4)
Aromatics Nomenclature
Br
Br
1,2-dibromobenzene
o-dibromobenzene
orthoA.
Aromatics Nomenclature
Br
Br
para1,4-dibromobenzenep-dibromobenzene
B.
Aromatics Nomenclature
Br
Br
meta1,3-dibromobenzene
m-dibromobenzene
C.
Aromatics Nomenclature
CH3
CH2CH3
3-ethyl-1-methylbenzeneD.
Substituted Hydrocarbons
1. Atoms of other elements can be joined to the carbons in place of one or more hydrogens.
2. Oxygen, nitrogen, sulfur and the halogens are the most common atoms that replace hydrogens.
3. The resulting compound is called a substituted hydrocarbon. 4. Sometimes a combination of two of these other elements will be
found in place of hydrogens. 5. These other elements give rise to what are called functional groups.
ALCOHOLS1. The most common of the functional groups 2. Contains an "- OH" group, which is known as the hydroxyl group 3. An aliphatic hydrocarbon that has one hydroxyl group attached to a
carbon is called an alcohol.
Alcohol Nomenclature
1. Select the longest carbon chain containing –OH group.2. Replace the -e ending of the parent alkane with -ol3. Number the alkane chain beginning at the end nearer the –OH
group.4. Number the attached groups according to their positionAlcohol Nomenclature
CH3
CH3
C OHCH3
2-methyl-2-propanol
A.
Alcohol Nomenclature
CH3CH2OH
ethanol
B.
Alcohol Nomenclature
CH3OH
methanol
C.
Alcohol Nomenclature
C C CC H
H
H
OH
H
H
H
H
HH
2-butanolD.
ETHERS 1. Results when there is an oxygen atom between two carbons in the chain 2. Ethers are represented as R-O-R', where R and R' can be the same or different hydrocarbon units.
Ether Nomenclature1. Identify the two attached groups and add the word ether.2. If there are more than 2 attached groups name as a benzene ring.
Ether Nomenclature
A.
CH3CH2 O CH3
Ethylmethyl etherEther Nomenclature
B.
CH3CH2 O CH2CH3
Diethyl ether
Aldehydes 1. A new class of substituted hydrocarbons arises when an oxygen atom is double bonded to the carbon at the end of the chain. 2. These compounds show the generic formula,
Aldehyde Nomenclature1. Replace the – e of the parent alkane with –al2. The longest chain selected includes the aldehyde group.3. The carbon in the aldehyde group is always numbered as the #1
carbon.
Aldehyde Nomenclature
A.
H C HO
MethanalAldehyde Nomenclature
B.
CH3 C HO
Ethanal
Ketones • A different class of organic compounds results if the C=O occurs somewhere along the chain other than on the end carbon • The generic formula for ketones is
Ketones•The generic formula for ketonesis
R C RO
Ketone Nomenclature1. Replace the – e of the parent alkane with – one2. The longest chain selected includes the ketone group.3. Numbering begins nearer the carbonyl carbon.
Ketone Nomenclature
A.
CH3 C CH3
O
propanoneKetone Nomenclature
B.
CH3 C CH2CH3
O2-butanone
Carboxylic Acids• Found a lot in nature formed by the oxidation of alcohols and aldehydes.• These compounds show the generic formula,
Carboxylic Acids•Found a lot in nature formed by
the oxidation of alcohols and aldehydes.
•These compounds show the generic formula, O
R C OH
Carboxylic Acid Nomenclature1. Carboxyl carbon is number one.2. Parent alkane – e is replaced with – oic acid
Carboxylic Acid Nomenclature
A.
CH3 CH2 C OHO
Propanoic Acid
Carboxylic Acid Nomenclature
B.
CH3CCHCH2CH2COH
CH3 O
5-methylhexanoic acid
Polymers 1. Large molecule formed by the covalent bonding of repeating
smaller molecules.2. Monomer: Smaller molecules that combine to form the repeating unit of a
polymer.3. Polymerization: Joining two or more monomers together creating a polymer.4. First synthetic polymer was nylon (1930s).5. Two methods synthesizing polymers are addition and condensation
polymerization.6. Addition: Unites thousands of monomers into a single enormous molecule 7. Condensation: Joining of two molecules (monomers) and the elimination of a small
molecule, usually water.
