Download Esters A class of organic compounds that react with water to

Esters
 A class of organic compounds that
react with water to produce
alcohols and organic and inorganic
acids.
 It is mainly result of condensation
of a carboxylic acid and an alcohol.
Physical Properties of Esters
1. Physical State : Lower molecular
weighted esters are colourless
volatile liquids.
2. Odour: All esters have a strong
fruity smell.
3. Solubility: Lower members of
esters are soluble in water . The
solubility decreases with increase
in molecular weight of the esters.
Esters are soluble in organic
solvents. Ester themselves are
good organic solvents.
4. Acidic nature: Esters are neutral.
5. Polarity: Esters are polar due to
the presence of carbonyl group
and act as hydrogen bond
acceptors not as donors.
Name
Melting
Point
(KELVIN)
Boiling
Point
(KELVIN)
Methyl
Acetate
175
330
Methyl
Formate
173
305
Ethyl
Acetate
190
350
Ethyl
Formate
193
327
Methyl
Benzoate
260.5
472.6
Ethyl
Benzoate
239
486
Uses of Esters
 Used as artificial perfumes or scents as
they emit a sweet smell.
 Used in making artificial food flavours
that are added in many edible items like
ice creams, softdrinks etc.
 Used as industrial solvents for making
cellulose, fats, paints and varnishes.
 Used as solvent in pharmaceutical
industries.
 Used as softeners in plastic industries
and molding industries.
Naming an Esters
 Identify the alkyl group that is
attached to the oxygen atom.
 Number according to the
closest to the -CO- group
regardless of where the alkyl
substituents are .
 Determine the alkane that
links the carbon atoms
together. If there is a
separation of a continuous
link of carbon atoms due to
the oxygen atom, individually
name the two alkanes before
and after the oxygen atom.
The longer the structural
alkane is the one that should
contain the carbonyl group.
 The format is as folows:
 (akane further from
carbonyl)(alkane closest
to carbonyl)(parent
chain)
 Change the parent chain –e
ending and replace it with an
–oate.
Examples...
Ester Name
Structure
Occurrence
Ethyl Acetate
Nail polish remover
Ethyl
Hexanoate
Pineapple, waxygreen banana
Methyl acetate
Glue
Octyl Acetate
Fruity Orange
 Ester’s Chemical Reaction
 Fischer Esterification