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DAMIETTA
UNIVERSITY
CHEM-103:
BASIC ORGANIC CHEMISTRY
LECTURE 2
Dr Ali El-Agamey
Common Alkyl Groups
2
Write the IUPAC names of the following compounds
3-Ethyl-5-methylheptane
3-Ethyl-4-methylhexane
  When the number could begin from both ends of the
chain, begin with the one that is alphabetically first.
3
Write the IUPAC names of the following compounds
2,2-Dimethylpropane
2,2,4-Trimethylpentane
3-Ethyl-4-methylheptane
5-Ethyl-2,4-dimethylheptane
3,7-Diethyl-2,2-dimethyl-4propylnonane
4
Write the IUPAC names of the following compounds
3-Ethyl-5-methylheptane
4-Ethyl-2,3-dimethyloctane
6-Ethyl-3,3-dimethyloctane
5
Homework: Write the IUPAC names of the
following compounds
6
Homework: Provide the IUPAC names for the
following compounds
7
Write the structures for the
following compounds
  (i) 3-Ethyl-4-methylhexane
  (ii) 3-Ethyl-5-isobutyl-3-methylnonane
  (iii) 4-tert-Butyl-2-methylheptane
  (iv) 5-Isopropyl-3,3,4-trimethyloctane
  (v) 4-Isopropyl-2,2,3,6-tetramethyloctane
8
Homework: Write the structures for
the following compounds
  (i) 2,2-dimethylbutane
  (ii) 2,2-dimethylpropane
  (iii) 6-ethyl-3,3-dimethyloctane
  (iv) 5-Isopropyl-3,3,4-trimethyloctane
  (v) 3-methyl-5-propylnonane
  (vi) 5-(1,2,2-Trimethylpropyl)nonane
  (vii) 2,2,4-Trimethylpentane
  (viii) 5-tert-Butyldecane
9
Write the correct IUPAC name of
the following compounds
  (i) 4-Ethylpentane
  (ii) 2-Ethylpentane
  (iii) 3-Isopropylpentane
  (iv) 2-Methyl-3-ethylpentane
10
Homework: Write the correct IUPAC
name of the following compounds
  (i) 2-Ethyl-3-methylpentane
  (ii) 3,4-Dimethylpentane
  (iii) 2-Isopropylhexane
  (iv) 3-methyl-5-ethylheptane
  (v) Isobutane
11
Nomenclature of cycloalkanes
1-Ethyl-2-methylcyclobutane
  If there are two or more substituents, the ring carbons are
numbered to give the lowest possible numbers.
  When the acyclic portion of the molecule contains more
carbon atoms than the cyclic portion (or when it contains
an important functional group) the cyclic portion is
named as a cycloalkyl sunstituent.
12
Homework: Write the IUPAC name of
the following compounds (a and b) and
the structures of i and ii
  (i) 1-Ethyl-3-methylcycloheptane
  (ii) Isobutylcyclohexane
13
Nomenclature of alkenes
IUPAC nomenclature
  (1) Parent name is alkene i.e. change the -ane to -ene.
  Choose the longest continuous chain containing the
double bond as the basis for the parent name.
  The position of the double bond takes the lowest
possible number.
  A compound with 2 double bonds is a diene. A triene has
3 double bonds, and a tetraene has 4.
IUPAC and New IUPAC
Chapter 7
15
Ring Nomenclature
In a ring, the double bond is assumed to
be between Carbon 1 and Carbon 2.
3
2
1
2
1
1-methylcyclopentene
3-methylcyclopentene
Chapter 7
16
Nomenclature of alkenes
Write the IUPAC name of the following compounds
but-1-ene
4-ethyl-3-methylcyclohexene
4-ethylhept-1-ene
cis-trans Nomenclature
cis-But-2-ene
trans-But-2-ene
cis-1,2-Dichloroethene
(m.p. = -80 oC)
trans-1,2-Dichloroethene
(m.p. = -50 oC)
  If two similar groups bonded to the carbons of the double
bond are on the same side of the bond, the alkene is the
cis isomer.
  If two similar groups are on opposite sides of the double
bond, the alkene is the trans isomer.
E-Z Nomenclature
2-methylbut-2-ene propene
(E)-1-bromo-1-chloropropene
  If it is not obvious which substituents are referred to as being
cis or trans, we use the E-Z system, which uses the CahnIngold-Prelog rules to assign the priorities of the groups.
  Priority depends on atomic number (greater atomic No.
leads to higher priority)
  Assign the 1st and 2nd priorities of the groups at each end of the
double bonds. If two 1st priority groups are together on the
same side of the double bond, you have the Z isomer.
  If two 1st priority groups are on opposite sides of the double
bond, you have the E isomer.
Nomenclature of alkenes
Write the IUPAC name of the following compounds
(E)-pent-2-ene
(E)-5-vinylnona-1,7-diene
(Z)-pent-2-ene
(3Z,5E)-3-bromoocta-3,5-diene
Nomenclature of alkynes
IUPAC nomenclature
  (1) Parent name is alkyne i.e. change the -ane to -yne.
  Choose the longest continuous chain containing the triple
bond as the basis for the parent name.
  The position of the triple bond takes the lowest possible
number.
  If both double and triple bonds are present, the ending
becomes –enyne and numbering is such as to give the
lowest possible numbers to the double and triple bonds,
irrespective of whether –ene or –yne has the lower
number. When either group can assigned the same
number, -ene has the higher priority.
Write the IUPAC name of the following compounds
ethyne
but-2-yne
6-bromo-2-methylhept-3-yne
propyne
4-methoxyhex-2-yne
2-methylpent-1-en-3-yne
Multifunctional Compounds
•  The functional group with the highest priority
determines the parent name.
Naming Priority:
acid > ester > amide > nitrile > aldehyde > ketone >
alcohol > amine > alkene > alkyne
Chapter 21
23
Nomenclature of aldehydes and ketones
IUPAC nomenclature
  Functional group
Name as substituent
  Nitriles
Cyano
  Aldehydes
Formyl
  Ketones
Oxo
  Alcohols
Hydroxy
  Amines
Amino
  Ethers
Alkoxy
  Halides
Halo
Chapter 21
25
Nomenclature of alcohols
IUPAC nomenclature
  (1) Parent name is alkanol
  Choose the longest continuous chain containing the
hydroxy group.
  Numbering begins at one end so as to give the hydroxy
group the lowest possible number.
  Alcohols with two –OH groups are called diols and
Alcohols with three –OH groups are called triols.
Examples of Nomenclature
OH
CH3
CH3
3
CH3
CH CH2OH
2
1
1
2-Methyl-1-propanol
2-Methylpropan-1-ol
CH3
CH CH2CH3
2
3
4
2-Butanol
Butan-2-ol
1 CH3
2
OH
C OH
CH2
3 CH3
5
2-Methyl-2-propanol
2-Methylpropan-2-ol
CHCH2CHCH3
4
3
2 1
4-penten-2-ol
pent-4-en-2-ol
Chapter 10
27
Write the IUPAC name of the following compounds
pentan-1-ol
1-bromo-3,3-dimethylbutan-2-ol
(E)-pent-2-en-1-ol
cyclohex-2-enol
1-cyclohexylbutane-1,3-diol
Homework: Write the IUPAC name of the following compounds
Nomenclature of aldehydes and ketones
IUPAC nomenclature
  (1) Ketones: Parent name is alkanone
  Choose the longest continuous chain containing the
carbonyl group.
  In cyclic ketones the carbonyl carbon atom is assigned
the number 1.
  (2) Aldehydes: Parent name is alkanal
  An aldehyde carbon is at the end of a chain, so it is
number 1.
  For cycloalkanes with aldehyde substituent, the suffix carbaldehyde is used.
Examples
O
1
CH3
3
4
C CH CH3
2
CH3
3-methyl-2-butanone
3
4-hydroxy-3-methyl-2-butanone
3-bromocyclohexanone
CH3
O
O
CH3
O
C
CH CH2
C H
2
CH2 CH CH2 C H
3
1
3-methylpentanal
3
Br
4
3
C CH CH2OH
2 CH
1
CH3
5
CH3
1 O
O
CH3
4
3
1
3-methyl-4-oxopentanal
31
Write the IUPAC name of the following compounds
1-phenylpropan-1-one
4-bromo-3-methylheptanal
(E)-pent-2-enal
cyclohexanecarbaldehyde
Homework: Write the IUPAC name of the following compounds
Nomenclature of carboxylic acids
IUPAC nomenclature
  Acids are named in IUPAC nomenclature as alkanoic
acid.
  Cycloalkanes with -COOH substituents are generally
named as cycloalkanecarboxylic acids.
Methanoic acid
Ethanoic acid
2-isopropyl-4-oxopentanoic acid
4-aminobutanoic acid
Nomenclature of carboxylic acids
IUPAC nomenclature
  Aliphatic dicarboxylic acids are named in IUPAC
nomenclature by adding the suffix –dioic acid.
  Choose the longest continuous chain that contains both
carboxyl groups. Numbering begins with the carboxyl
group that is closer to the substituents.
3-bromohexanedioic acidcyclopentane-1,3-dicarboxylic acid
Homework: Write the IUPAC name of the following compounds
Nomenclature of Esters
isopropyl methanoate
•  Esters are named as alkyl carboxylates.
•  The first word is derived from the alkyl group of the
alcohol, and the second word is derived from the
carboxylic acid by changing -ic acid to –ate.
Chapter 21
37
Nomenclature of Esters
IUPAC nomenclature
Ethyl butanoate
Methyl 3-bromo-2-methylbutanoate
Nomenclature of Amides
IUPAC: N-Ethylethanamide
Common: N-Ethylacetamide
IUPAC: N,N-Dimethylmethanamide
Common: N,N-Dimethylformamide
•  For 1° amide, first name the corresponding
acid. Drop -ic acid or -oic acid from the
carboxylic acid name and add -amide.
•  For 2° and 3° amides, treat the alkyl groups on
nitrogen as substituents, and specify their
position by the prefix N-.
39
Chapter 21
Nomenclature of Amides
IUPAC: N-Ethyl-N,2-dimethylpropanamide
Common: N-Ethyl-N-methylisobutyramide
IUPAC: Cyclopentanecarboxamide
 For cycloalkanes with amide substituent,
the suffix -carboxamide is used.
Chapter 21
40
Homework: Write the IUPAC name for each of the following
compound