Organic Chemistry

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Organic Chemistry
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Organic Chemistry

• Chemical compounds fall into one of two
  categories
• Organic compounds
• Inorganic compounds
• Organic compounds can be found naturally or they
  can be synthesized, but they all contain C and a
  few other elements.
• There are far more organic compounds than
  inorganic compounds.

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Organic Compounds

• fuels
• carbohydrates, fats, proteins
• vitamins
• penicillin, sulfa drugs

• plastics
• cotton, silk, wool
• rubber
• DNA
• ibuprofen, aspirin, morphine

Organic chemistry is part of our everyday lives!
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Properties of Organic Compounds

• usually molecular (contain non-metals bonded with
  covalent bonds)
• low melting points
• nonpolar (insoluble, or only slightly soluble, in
  water)
• very stable (not reactive)

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Carbon

• Carbon forms 4 covalent bonds, i.e., it will
  share electrons with 4 other elements.
• Prefixes are used in the name to indicate how
  many carbons are in the compound.

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Carbon Prefixes
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Memory Aid

• Many Equestrian People Buy Pretty Handsome Horses
  Of Noble Descent.

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Naming Alkanes
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Alkanes

• Alkanes are hydrocarbons (consisting of only C
  and H) that only contain single bonds.
• Start with the Prefix that matches the number of
  carbons
• Alkanes have the ending ane in their name.

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CH4

• Draw the structural formula

One carbon is meth ane ending So this is
Methane
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C2H6

• Draw the structural formula

Two carbons is eth ane ending So this is
Ethane
May also be drawn as CH3-CH3
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C3H8

• Structural formula

Three carbons is prop ane ending So this is
Propane
HI
HI
HI
CCC
H
H
IH
IH
IH
May also be drawn as CH3-CH2-CH3
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C4H10

• There are two possible structural formulas

HI
HI
HI
HI
This is n-butane because it is a straight chain
CCCC
H
H
IH
IH
IH
IH
May also be drawn as CH3-CH2-CH2-CH3
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OR
This is 2-methyl propane because there is a
methyl side group off of the 2nd carbon in the
propane chain.
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Isomers

• are compounds that have the same molecular
  formula, but different structural formulas.
• Isomers usually have different chemical and
  physical properties as well.
• We must have some way of specifying which form of
  butane we are talking about.

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Normal Alkanes

• Alkanes that have a continuous chain of carbons
  are called normal alkanes.
• The first isomer of butane is a normal alkane and
  is sometimes referred to as n-butane.

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Branched Alkanes

• The second isomer has a branch off the second
  carbon.
• These branches are referred to as alkyl groups.
• The name of the alkyl group is determined by the
  prefix according to the number of carbons and the
  ending -yl
• The branch in this case would be called methyl

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Rules for Naming Alkanes

• Count the carbons of the longest continuous
  chain. This will be the prefix. Add ane to it.
  
• Name the alkyl groups attached to the main chain.
  If there are two or more of the same name, use
  the counting prefixes (di, tri, etc.)

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Rules for Naming Alkanes, contd

• Number the carbons, starting with the carbon
  closest to the branch.
• List the alkyl groups first, in alphabetical
  order, using a number to indicate which carbon it
  branches from.

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This would be called 2-methyl propane
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This is a short-hand way of writing the same
formula