Organic chemistry
Thidr lecture
Alkanes
Alkanes are the compounds that contain only carbon and hydrogen atoms and
contain only single bonds, the general molecular formula for alkane is (C nH2n+2).
* n = number of carbon atoms
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Organic chemistry
Thidr lecture
Nomenclature
Common name
systematic name
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Organic chemistry
Thidr lecture
Systematic nomenclature is also called IUPAC nomenclature
(Introduction Union of Pure and Applied Chemistry)
* removing a Hydrogen from an alkane results in an alkyl substituent or alkyl
group.
1) Determine the number of carbons in the longest
continuous carbon chain. This chain is called the
parent hydrocarbon.
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Organic chemistry
Thidr lecture
2) The name of any alkyl substituent that hangs off the parent hydrocarbon is cited
before the name of the parent hydrocarbon, together with a number to designate
the carbon to which the alkyl substituent is attached. The chain is numbered in
the direction that gives the substituent as low a number as possible.
If more than one substituent is attached to the parent hydrocarbon, the chain is
numbered in the direction that will result in the lowest possible number in the
name of the compound.
3)
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Organic chemistry
Thidr lecture
* If two or more substituents are the same, the prefixes “di,”“tri,”and “tetra”
are used to indicate how many identical substituents the compound has.
4) If the same substituent numbers are obtained in both directions, the first group
cited receives the lower number.
5) When both directions lead to the same lowest number for one of the
substituents, the direction is chosen that gives the lowest possible number to
one of the remaining substituents.
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Organic chemistry
Thidr lecture
Ex. Nomenclature of Cycloalkanes
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Organic chemistry
Thidr lecture
PROBLEM-1-
PROBLEM-2-
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