Transcript Essential oil

Starter activity
What’s the most pleasant smell
you can think of?
And the most revolting?
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Making and testing perfumes…
Chanel No.5
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Scent facts
• Dogs can detect the difference in smell between
non-identical twins AND between identical twins
despite the fact they are given the same foods or
live in the same environment. (Search Dogs)
• Since Moths lack a nose, they use their antenna for
smell. Some male moths can detect a single
molecule of a female moth’s sex hormone up to 7
miles (11 km) away. A dozen molecules drives the
male crazy!
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Perfume facts
One of the key scents in many male aftershaves is musk,
which was originally extracted from glands (called a musk
pod) that produce pheromones on the male musk deer.
Synthetic forms used now.
In May 1921, when the perfume creator Ernest Beaux
presented her with a choice of fragrances, Gabrielle Chanel
barely hesitated before choosing the fifth one, which was to
become CHANEL N°5.
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What Chemicals are in
Perfumes?
•
•
•
•
•
•
•
•
•
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Aliphatic & Aromatic Esters
Aldehydes & Ketones
Alcohols
Terpenes
Phenols
Nitriles
Lactones
Heterocyclics
Acids
Sulphur compounds
Commercial Fragrances
Hydrocarbons
4%
Musks
6%
Other
8%
Esters
34%
Ketones
10%
Aldehydes
15%
Alcohols
23%
Properties of Perfume:
Why does a perfume need these
properties?
• Volatile
– Low Molecular Weight
– Evaporates easily
• Non-toxic
– Will not poison the wearer
• Does not dissolve in water
– Prevents sweating it off
• Does not irritate the skin
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What is diffusion?
Diffusion is the movement of
particles that allows them to spread
out and mix with other particles.
For example, the smell of aftershave
or perfume diffuses and is detected by
people on the other side of the room.
Use the particle model to explain these facts about diffusion:
 Diffusion occurs in liquids and gases but hardly at all in
solids.
 Diffusion happens more quickly for gases than for liquids.
 Diffusion happens more quickly at warm temperatures
than at cooler temperatures.
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© Boardworks Ltd 2005
2004
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Diffusion animation 1
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Diffusion
Diffusion is when something travels from an area of high
concentration to an area of low concentration. For example,
consider the scent from a hamburger…
The “scent particles” from
this hamburger are in high
concentration here:
Eventually they will
“diffuse” out into this area
of low concentration:
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How do our Olfactory sensors
work?
• GAS particles DIFFUSE up our NOSE
• Inside the Nose: A patch of tiny Neurons the size
of a postage stamp with cilia
• Molecules bind to the cilia
Artificial Nose Video
• Trigger receptors that signal the brain to perceive a smell
• Differently shaped nerve cells recognize different smells because
each smell molecule fits into a nerve cell like a lock and key
• Each receptor is encoded with a specific gene - if mutated, certain
smells are not recognized
Periodic Table of SmellElements
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Keywords
synthetic
This is when liquid particles have
enough energy to turn into gas
particles
pungent
This means something will not
dissolve
diffusion
A type of chemical made when an
alcohol is mixed with an acid
ester
A perfume that is
made using man made chemicals
insoluble
A very strong (and unpleasant) smell
evaporate
This is the movement of particles
from an area of high concentration
to an area of low concentration
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Keywords
synthetic
A perfume that is
made using man made chemicals
pungent
A very strong (and unpleasant) smell
diffusion
This is the movement of particles
from an area of high concentration
to an area of low concentration
ester
A type of chemical made when an
alcohol is mixed with an acid
insoluble
This means something will not
dissolve
evaporate
This is when liquid particles have
enough energy to turn into gas
particles
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O
Esters
AROMATICS
Found in Fats and
Oils

CH3 —C—O—CH3
ester group
What are they?
How are they made?
Formed when an alcohol reacts with a
carboxylic acid.
Very slow reaction, unless! an acid catalyst
used (usually sulfuric acid)
A condensation reaction
The condensation reaction between the hydroxyl
group and the carboxylic acid known as
esterification.
Reverse reaction = ester hydrolysis
R
O
+
H
O
C
H
O
R’
⇋
O
C
R
R’
O
This is why it is a
condensation reaction
because water is produced!
+
H2O
Definition of a condensation reaction =
two molecules reacting to form a larger
molecule with the elimination of a
small molecule such as water
Names of esters
end in –oate.
Naming
Named after alcohol & carboxylic acid
from which they are derived.
O
C
CH3
CH2
CH3
let’s name
some esters!
O
ethyl
this part comes from the
alcohol & is named after
it
- “ol” becomes “yl”
ethanoate
this part from the acid
and is named after it
NAMING ESTERS
NAME THE FOLLOWING ESTERS.
1. Methanol and Methanoic Acid
2. Ethanol and Ethanoic Acid
3. Butan-1-ol and Methanoic Acid
4. Ethanol and Hexanoic Acid
Answers:
Structural formula
Although the previous structural formula are the clearest
way of showing esters, they can draw out in a
shortened form.
In this version
ethyl ethanoate
O
Either…
CH3 CH2
O
C
CH3
Or…
O
CH3 C
the acid part
has been
written first
O
CH2
CH3
 Identify the group attached to the C=O – this is from
the acid
 The group attached to the –O- is from the alcohol.
Wait! What’s that smell?
ester
ethyl methanoate
3-methylbutyl ethanoate
ethyl 2-methylbutanoate
phenylmethyl ethanoate
fragrance
raspberries
pears
apples
jasmine
• Esters have strong, sweet smells.
• Their bouquet is often floral or fruity.
• This means they are used in food flavorings &
perfumes.
• Also, very good at dissolving organic compounds so
often used as solvents.
Esters from phenols
• -OH group in phenol less reactive
to esterification, requires a more
vigorous reagent.
• Use of ethanoic acid in
esterification is also known as
ethanoylation.
• Ethanoic anhydride is a more
vigorous ethanoylating agent
OH
Esters from phenols
• Ethanoic anhydride used as it is reactive
but not too dangerous.
• Ethanoyl chloride is much more reactive,
but, also toxic and hazardous to use.
• Ethanoic anhydride & ethanoyl chloride
are described as acylating agents
using an acylating agent is the only way to esterify a
phenol
alcohols can be esterified using acylating agents or by
reacting with a carboxylic acid.
O
CH
CH3
CH2
ethyl
methanoate
O
O
C
CH3
CH2
CH3 methyl
propanoate
O
O
CH
CH3
O
methyl
methanoate
FORWARD REACTION = condensation reaction,
the esterification of an alcohol using
acid catalyst under reflux.
R
O
+
H
O
C
H
O
R’
⇌
O
C
R
R’
O
+
H2O
REVERSE REACTION = ester hydrolysis, same
catalyst works for both forward & reverse
reactions.
ethanol
ethyl ethanoate
O
CH3 CH2
O
C
+
OH-
CH3
→
CH3 CH2
+
O
-O
not a reaction that exists
in equilibrium (unlike
using acid catalyst)
OH
C
CH3
ethanoate ion
Essential Oils
contain Esters
What are Essential Oils?

Essential oils are the concentrated extracts
of volatile, non-water-soluble aroma
compounds from PLANTS.

Essential oils are widely used in
PERFUMES, cosmetic products, cleaning
products and as flavorings in FOODS.
ESSENTIAL OILS

Essential oils are mixtures of organic
compounds. Contain Carbon.

TERPENES are the key components in
most essential oils.
The history of essential
oils

The benefits of essential oils have
been recognized for thousands of
years.

Their use is described in the New
Testament of the Bible.

They were used in anointing
rituals and in HEALING THE SICK.
The history of essential
oils

The ancient Egyptians used
essential oils for EMBALMING
RELIGIOUS RITES and
MEDICINAL purposes.

KING TUT’S tomb was found to
contain 50 jars of essential oil when
it was opened in 1922.
Modern uses
Cosmetics
Cleaning
Flavours
Dentistry
Essential oils
Adhesives
Insect
repellents
Medical
Perfumes
What are essential oils?

‘Essential’ refers to the fact that the oil carries the
distinctive essence (SCENT) of the plant.

Concentrated, volatile, non-water soluble aroma
compounds extracted from plants.

Contain NO ARTIFICIAL SUBSTANCES, unlike
perfumes and fragrance oils.
Essential oils – Chemistry

The distinctive character of an
essential oil can be attributed to the
functional group present in its key
molecule.

Esters, aldehydes, ketones and
alcohols are all found in essential
oils.
Medicinal Purposes of Essential Oils




Essential oils containing
a significant percentage
of esters are
antispasmodic.
Oils high in esters have
a pronounced sedative
effect.
Oils high in esters can
often be emotionally
uplifting.
Some are analgesic

Jasmine, Lavender,
Medicinal Purposes

Adaptogenic

helps the body adjust to and
deal with stress

Anti-inflammatory, and
effective on skin rashes
and skin irritations.

Some are good digestive
aids

Chamomile
MASSAGE
THERAPY
USING
ESSENTIAL
OILS
ESSENTIAL OILS: PRESCRIPTION ALTERNATIVES
Essential oils – Perfume

The ester linalyl acetate is found in the essential oil
lavender.

This ester is often added to perfumes.
H3C
C
CH3
O
C
H3C
CH2
CH
O
CH3
C
CH2
Linalyl acetate
CH2
CH
Essential oils – Cosmetics

The essential oil Geraniol is added to some
cosmetics to balance and revitalize the skin.
CH3
CH3
C
H3C
C
CH2
CH
CH2
Geraniol
CH2
CH
OH
Essential oils – Cleaning

The essential oil known as lemon oil contains the
terpene d-limonene.

It is known for its ability to act as a natural solvent
and a cleanser.
H3C
CH2
C
CH
H2C
CH2
H2C
CH
C
CH3
Limonene
(skin of citrus fruits)
Hospital Cleaners

Certain essential oils kill bacteria and fungi
including MRSA -Staph and E. coli within 2
minutes of contact.

Essential oils are blended into soaps and
shampoos used in hospitals to eradicate deadly
‘super bugs’.
Essential oil – Cold Sores

Melissa oil contains the terpene
citral, which is used to combat cold
H
CH3
sores.
CH3
C
H3C
CH
CH2
C
C
CH2
Citral
CH
O
Essential oils – Toothpaste
& Foot Fungus Treatment

The essential oil Thymol has antiseptic
properties.
CH3
C
HC
CH
C
CH
HO
C
CH
H3C
Thymol
CH3
Steam distillation

Steam distillation is one of the methods used to
extract essential oils from plants.

Steam passes over the plant and extracts the
essential oil.

The mixture evaporates and passes into the
condenser.

The essential oil vapor is chilled and collected.
Steam distillation
Essential Oils
Safety
Should Always
be
Considered