Esters are compounds derived from acids where a hydroxyl group is replaced by an alkoxy group. They have the functional group R-C(=O)-O-R'. Esters are prepared through the reaction of carboxylic acids with alcohols. Their names indicate the parent alcohol and acid. Esters have lower boiling points than the corresponding acids and alcohols. They undergo hydrolysis and saponification reactions. Common esters include benzocaine which is used as a local anesthetic, aspirin which is used as a pain reliever and fever reducer, and oil of wintergreen which contains methyl salicylate used to treat pain.

1. ESTERS

2. ❑is a chemical compound
derive from an acid in which
at least one —OH (hydroxyl)
group is replaced by an
—O—alkyl (alkoxy) group.

3. STRUCTURE
OF
ESTERS

4. O
║ Ester
R ─ C ─ O ─ R

5. ❑The functional group of ester :
O
║
—C—O—R

6. ❑ In linear form, the ester functional
group can be represented as
—COOR or —CO2R.
O
║
H ─ C─ O ─ CH3

7. PREPARATION
OF ESTERS

8. reaction of carboxylic acid
with an alcohol (or phenol) to
produce an ester.

10. NOMENCLATURE FOR
ESTERS

11. Rule 1: The name for the
alcohol part of the ester
appears first and is followed by
a separate word giving the
name for the acid part of the
ester.

12. Rule 2: The name of the
alcohol part of the ester is
simply the name of the R
group (alkyl, cycloalkyl, or aryl)
present in the –OR portion of
the ester.

13. Rule 3: The name for the acid
part of the ester is obtained by
dropping the –ic acid ending
for the acids name and adding
the suffix –ate.

14. Cyclic Esters (Lactones)
— Hydroxyl acids compounds which
contain both a hydroxyl and a
carboxyl group have the capacity
to undergo intermolecular
esterification to form cyclic esters.

15. PHEROMONES

16. ❑Is a chemical an animal
produces which changes the
behavior of another animal of
the same species (animals
including insects).

19. MEDICATION

20. Benzocaine
― a white, odorless, crystalline
powder used in ointments as a
local anesthetic and to protect
against sunburn

22. USES OF BENZOCAINE:
■Used to reduce pain cause by
minor skin irritations, sore throat,
sunburn, teething pain, vaginal
irritation, ingrown and many
other sources of minor pain on a
surface of the body

24. Aspirin
-is also known as
acetylsaliccyclic acid
-is a medication used to treat
pain,fever or inflamation

26. Structure of Aspirin:

27. USES OF ASPIRIN:
■Used to reduce fever and
relieve mild to moderate pain.
■It may also used to reduced
pain and swelling in conditions
such as arthritis

28. Oil of Wintergreen
-is an organis ester naturally
produced by many species of
plants, particularly wintergreens.

30. USES OF OIL OF
WINTERGREEN:
■Used for painful condition
including nerve pain, ovarian
pain and menstrual cramps

31. STRUCTURE OF OIL OF
WINTERGREEN:

32. Isomerism for Esters

33. Ester positional isomer:
O
║
CH3–CH2–C–O–CH3
Methyl propanoate

34. O
║
CH3–C–O–CH2–CH3
Ethyl ethanoate

35. Ester functional group isomers:
O
║
CH3–CH2–C–O–CH2–CH3
Ethyl propanoate

36. PHYSICAL PROPERTIES
OF ESTERS

37. ❑Ester molecules cannot
form hydrogen bonds to
each other

38. ❑Boiling points are much
lower than alcohol and
carboxylic acids

39. CHEMICAL REACTIONS OF
ESTERS:
●Ester hydrolysis
●Ester saponification
(Depending on reaction
condition)

40. Ester Saponification
- is the hydrolysis of an organic
compound under basic conditions
in which a carboxylic acids salt is
one of the products.

41. THANK YOULYKA ROSE TAOTAO
ALTHEA ARGUILLES
ROM HARVY BERNALTE
______________________________
SOGOD NATIONAL HIGHSCHOOL
_______________________________
GENERAL, ORGANIC and BIOLOGICAL
CHEMISTRY 6TH EDITION, STEHPEN
STOKER