Structure and Uses of Different alkyl halides are discussed

1. Structure and uses of
different Alkyl halides
by
Dr. Nidhi Gupta
M.M. College of
Pharmacy
Mullana, Ambala,
India

2. Ethyl chloride
• Chloroethane or mono chloroethane, commonly known by its old
name ethyl chloride, is a chemical compound with chemical formula
• C 2H5Cl, once widely used in producing tetraethyllead, a gasoline additive. It
is a colourless, flammable gas or refrigerated liquid with a faintly sweet
odour.

3. Ethyl chloride

4. Uses
• Like other chlorinated hydrocarbons, chloroethane has been used as a refrigerant,
an aerosol spray propellant, an aesthetic, and a blowing agent for foam packaging.
For a time it was used as a promoter chemical in the aluminium chloride catalysed
process to produce ethylbenzene, the precursor for styrene monomer. At present
though, it is not widely used in any of these roles.
• The only remaining industrially important use of chloroethane is in
treating cellulose to make ethyl cellulose, a thickening agent and binder
in paints, cosmetics, and similar products.
• Chloroethane is supplied as a liquid in a spray bottle propelled by its own vapor
pressure.

5. Chloroform
• Chloroform, or trichloroethane, is an organic
compound with formula CHCl3. It is a colourless, sweet-smelling, dense
liquid that is produced on a large scale as a precursor to PTFE. It is also a
precursor to various refrigerants. It is one of the four chloromethanes and
a trihalomethane.

6. • The molecule adopts tetrahedral molecular geometry with
C3v symmetry.

7. Uses
• Solvent
• The hydrogen attached to carbon in chloroform participates in hydrogen bonding. Worldwide,
chloroform is also used in pesticide formulations, as a solvent
for fats, oils, rubber, alkaloids, waxes, gutta-percha, and resins, as a cleansing agent,
grain fumigant, in fire extinguishers, and in the rubber industry. CDCl3 is a common solvent
used in NMR spectroscopy.
• Reagent
• As a reagent, chloroform serves as a source of the dichlorocarbene CCl2 group. It reacts with
aqueous sodium hydroxide usually in the presence of a phase transfer catalyst to
produce dichlorocarbene, CCl2. This reagent effects ortho-formylation of activated aromatic
rings such as phenols, producing aryl aldehydes in a reaction known as the Reimer–Tiemann
reaction. Alternatively, the carbene can be trapped by an alkene to form a cyclopropane derivative.
In the Kharasch addition, chloroform forms the CHCl2 free radical in addition to alkenes.

8. Tetrachloroethylene
• Tetrachloroethylene, also known under the systematic
name tetrachloroethene, or perchloroethylene ("perc" or "PERC"), and
many other names, is a chlorocarbon with the formula Cl2C=CCl2. It is a
colourless liquid widely used for dry cleaning of fabrics, hence it is
sometimes called "dry-cleaning fluid".

10. Uses
• Tetrachloroethylene is an excellent solvent for organic materials. Otherwise it
is volatile, highly stable, and non-flammable. For these reasons, it is widely
used in dry cleaning. It is also used to degrease metal parts in
the automotive and other metalworking industries, usually as a mixture with
other chlorocarbons. It appears in a few consumer products including paint
strippers and spot removers.
• It is used in neutrino detectors where a neutrino interacts with a neutron in
the chlorine atom and converts it to a proton to form argon.

11. Trichloroethylene
• The chemical compound trichloroethylene is a halocarbon commonly used
as an industrial solvent. It is a clear non-flammable liquid with a sweet smell.
• The IUPAC name is trichloroethene. Industrial abbreviations
include TCE, trichloro, Trike, Tricky and tri. It has been sold under a
variety of trade names. Under the trade names Trimar and Trilene,
trichloroethylene was used as a volatile aesthetic and as an inhaled
obstetrical analgesic in millions of patients.

13. Uses
• TCE has also been used in the United States to clean kerosene-fueled rocket
engines (TCE was not used to clean hydrogen-fueled engines such as
the Space Shuttle Main Engine).
• It has also been used as a dry cleaning solvent, although replaced in the
1950s by tetrachloroethylene (also known as perchloroethylene), except for
spot cleaning where it was used until the year 2000.

14. Tetrachloromethane
• Carbon tetrachloride, also known by many other names (the most notable
being tetrachloromethane, also recognized by the IUPAC, carbon Tet in
the cleaning industry, Halon-104 in firefighting, and Refrigerant-
10 in HVACR) is an organic compound with the chemical formula CCl4. It
was formerly widely used in fire extinguishers, as a precursor
to refrigerants and as a cleaning agent. It is a colourless liquid with a "sweet"
smell that can be detected at low levels. It has practically no flammability at
lower temperatures.

16. Uses
• Lava Lamps
• Carbon tetrachloride is a key ingredient in lava lamps, as it adds weight to the otherwise buoyant wax.
• Solvent
• It once was a popular solvent in organic chemistry, but, because of its adverse health effects, it is rarely
used today. It is sometimes useful as a solvent for infrared spectroscopy, because there are no significant
absorption bands > 1600 cm−1. Because carbon tetrachloride does not have any hydrogen atoms, it was
historically used in proton NMR spectroscopy. In addition to being toxic, its dissolving power is low. Its
use has been largely superseded by deuterated solvents. Use of carbon tetrachloride in determination of
oil has been replaced by various other solvents, such as tetrachloroethylene. Because it has no C-H bonds,
carbon tetrachloride does not easily undergo free-radical reactions.
• Fire suppression

17. Dichloromethane
• Dichloromethane (DCM, or methylene chloride) is an organic
compound with the formula CH2Cl2. This colourless, volatile liquid with a
moderately sweet aroma is widely used as a solvent. Although it is
not miscible with water, it is miscible with many organic solvents.

19. Uses
• DCM's volatility and ability to dissolve a wide range of organic compounds
makes it a useful solvent for many chemical processes.
• It is widely used as a paint stripper and a degreaser. In the food industry, it
has been used to decaffeinate coffee and tea as well as to prepare extracts
of hops and other flavourings. Its volatility has led to its use as an aerosol
spray propellant and as a blowing agent for polyurethane foams.

20. Iodoform
• Iodoform is the organ iodine compound with the formula CHI3. A pale
yellow, crystalline, volatile substance, it has a penetrating and distinctive
odour (in older chemistry texts, the smell is sometimes referred to as the
smell of hospitals, where the compound is still commonly used) and,
analogous to chloroform, sweetish taste. It is occasionally used as
a disinfectant. It is also known as tri-iodomethane, carbon triiodide, and
methyl triiodide.

21. Uses
• The compound finds small-scale use as a disinfectant. Around the beginning
of the 20th century, it was used in medicine as a healing and antiseptic
dressing for wounds and sores, although this use is now superseded by
superior antiseptics. Adolf Hitler's mother, Klara Hitler, was treated with
iodoform. Some have suggested that she died of iodoform poisoning, but
metastasizing breast cancer was likely the primary cause of death. It is the
active ingredient in many ear powders for dogs and cats, along with zinc
oxide and propanoic acid, which are used to prevent infection and facilitate
removal of ear hair.

22. Thankyou