Simple Organic Chemistry

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Simple Organic Chemistry

• Basic Structure and Nomenclature

Graphic www.lab-initio.com
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First Ten Alkanes
Formula Name Formula Name
CH4 Methane C6H14 Hexane
C2H6 Ethane C7H16 Heptane
C3H8 Propane C8H18 Octane
C4H10 Butane C9H20 Nonane
C5H12 Pentane C10H22 Decane
Alkane CnH2n2
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Straight Chain Alkanes arent Straight
C C bonds are sp3 hybridized
Butane, C4H10
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Structural Shorthand
Explicit hydrogens (those required to complete
carbons valence) are usually left off of
drawings of hydrocarbons
C1
C2
C3
C4
C1
C3
C4
C2
Line intersections represent carbon atoms
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Structural Isomers
Isomers are molecules with the same chemical
formula, but different organization of atoms
(different bonding)
n-Pentane, C5H12
Isopentane, C5H12
Neopentane, C5H12
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Newman Projections
Rotation can occur around C C single bonds
Ethane, C2H6
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Newman Projections
Butane, C4H10
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Cyclic Alkanes
Cyclopropane, C3H6
Cyclobutane, C4H8
Cyclopentane, C5H10
Cyclohexane, C6H12
Cycloheptane, C7H14
Remember, explicit hydrogens are left out
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Rules for Naming Alkanes (Nomenclature)

• For a branched hydrocarbon, the longest
  continuous chain
• of carbon atoms gives the root name for the
  hydrocarbon

1
2
3
4
4 carbon chain butane
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Rules for Naming Alkanes (Nomenclature)

• When alkane groups appear as substituents, they
• are named by dropping the -ane and adding -yl.

CH3 Methyl
CH2CH3 Ethyl
CH2CH2CH3 Propyl
CH2CH2CH2CH3 Butyl
Methyl
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Rules for Naming Alkanes (Nomenclature)

• The positions of substituent groups are specified
• by numbering the longest chain of carbon atoms
• sequentially, starting at the end closest to the
• branching.

1
2
3
4
Methyl
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Rules for Naming Alkanes (Nomenclature)

• The location and name of each substituent are
• followed by the root alkane name. The
  substituents
• are listed in alphabetical order (irrespective of
  any
• prefix), and the prefixes di-, tri-, etc. are
  used to
• indicate multiple identical substituents.

1
2
3
4
Name
2-methylbutane
Methyl
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Nomenclature Practice
Name this compound
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9 carbons nonane
2
4
3
5
6
7
8
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• Step 1 For a branched hydrocarbon, the longest
  continuous chain of carbon atoms gives the root
  name for the hydrocarbon

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Nomenclature Practice
Name this compound
9 carbons nonane
1
2
4
3
5
6
CH3 methyl
7
chlorine chloro
8
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Step 2 When alkane groups appear as
substituents, they are named by dropping the -ane
and adding -yl.
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Nomenclature Practice
Name this compound
9 carbons nonane
1
2
4
3
5
6
CH3 methyl
7
chlorine chloro
8
9
1
9
NOT
9
1

• Step 3 The positions of substituent groups are
  specified by numbering the longest chain of
  carbon atoms sequentially, starting at the end
  closest to the branching.

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Nomenclature Practice
Name this compound
9 carbons nonane
1
2
4
3
5
6
CH3 methyl
7
chlorine chloro
8
9
2-chloro-3,6-dimethylnonane

• Step 4 The location and name of each
  substituent are followed by the root alkane name.
  The substituents are listed in alphabetical order
  (irrespective of any prefix), and the prefixes
  di-, tri-, etc. are used to indicate multiple
  identical substituents.

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Alkenes Contain Carbon-CarbonDouble bonds
1 ? bond
Ethene
1 ? bond
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Alkynes Contain Carbon-CarbonTriple Bonds
1 ? bond
Ethyne
1 ? bond
1 ? bond
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Reactions of Alkenes and Alkynes
Hydrogenation
Propene
Propane
Halogenation
1-Pentene
1-2-dibromopentene
Polymerization
Small molecules are joined together to form a
large molecule
Polyethylene
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Aromatic Hydrocarbons
Cyclic unsaturated hydrocarbons with delocalized
electrons
The simplest aromatic hydrocarbon is benzene
(C6H6)
OR
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Geometric Isomerism in Aromatics
ortho (o-) two adjacent
substituents
o-dichlorobenzene
meta (m-) one carbon between
substituents
m-dichlorobenzene
para (p-) two carbons between
substituents
p-dichlorobenzene
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Hydrocarbon Derivatives Hydrocarbon Derivatives Hydrocarbon Derivatives
Class Functional Group General Formula
Alcohol hydroxyl group -O H R OH
Alkyl halide X R X
Ether O R O R
Aldehyde carbonyl group O C H O R C H
Ketone carbonyl group O C O R C R
Carboxylic acid carboxyl group O C OH O C OH
Ester O C O O R C O R
Amine amine group N R R N R