Manufactured MeterialAromatic Compounds

BENZENEPHENOLMETHYL

BENZYNE BENZOIC

ACID

Nasrul Muhaimi

n

RajaHafizi

Learning Outcomes1.1 State types of aromatic compound

1.2 State the reactions of aromatic compounds

1.3 Explain the properties of aromatic compounds

1.4 State the uses of aromatic compound in daily life

BENZENE

Benzene is an organic chemical compound with the molecular formula C6H6

It is a natural constituent of crude oil, and may be synthesized from other compounds present in petroleum. 

It is an aromatic hydrocarbonIt is also related to the functional group arene which is a generalized structure of benzene.

Structure of Benzene

Benzene is a colorless andhighly flammable liquid with a sweet smell and a relatively high melting point

Because it is a known carcinogenits use as an additive in gasoline is now limited

It is an important industrial solvent and precursor in the production of drugs, plastics, synthetic rubber, and dyes

• Electrophilic aromatic substitution is a general method of derivatizing benzene.

• The Friedel-Crafts acylation is a specific example of electrophilic aromatic substitution

Reactions of Benzene

• The reaction involves the acylation of benzene (or many other aromatic rings) with an acyl chloride using a strong Lewis acid catalyst such as aluminium chloride or iron chloride which act as a halogen carrier.

• Like the Friedel-Crafts acylation, the Friedel-Crafts alkylation involves the alkylation of benzene (and many other aromatic rings) using an alkyl halide in the presence of a strong Lewis acid catalyst

• Aromatic sulfonation is an organic reaction in which a hydrogen atom on an arene is replaced by a sulfonic acid functional group in an electrophilic aromatic substitution.

Uses of Benzene

• Benzene is mainly used as an intermediate to make other chemicals.

• Its most widely-produced derivatives include styrene, which is used to make polymers and plastics, phenol for resins and adhesives (via cumene), and cyclohexane, which is used in the manufacture of Nylon.

• Smaller amounts of benzene are used to make some types of rubbers, lubricants dyes, detergents, drugs, explosives, napalm and pesticides.

Napalm Drugs

Pesticides

PHENOL

• Phenol is found naturally in decaying dead organic matter like rotting vegetables and in coal.

• It was first isolated in 1834 from coal tar and this remained the main source of phenol until the First World War.

• The first synthetic method was then devised and

all of the phenol today is man made

• Phenol, also known as carbolic acid, is an organic compound with the chemical formula C6H5OH.

• It is a white, crystalline solid. This functional

group consists of a phenyl, bonded to a hydroxyl (-OH).

Properties of Phenol Phenol is a colorless or white crystalline solid when it is pure; however, it is usually sold and used as a liquid.

The odor threshold for phenol is 0.04 parts per million (ppm), with a strong very sweet odor reported.

Phenol is very soluble in water and is quite flammable.

Its melting point is 43° C and its boiling point is182° C.

The vapor pressure for phenol is 0.3513 mm Hg at 25 °C, and it has a log octanol/water partition coefficient (log Kow) of 1.46.

Phenol is highly reactive toward electrophilic aromatic substitution as the oxygen atom's pi electrons donate electron density into the ring.

By this general approach, many groups can be appended to the ring, via halogenation, acylation, sulfonation, and other processes.

Reactions of Phenol

The primary use of phenol is in the production of phenolic resins, which are used in the plywood, construction, automotive, and appliance industries.

Phenol is also used in the production of caprolactam and bisphenol A, which are intermediates in the manufacture of nylon and epoxy resins, respectively.

Uses of Phenol

Other uses of phenol include as a slimicide, as a disinfectant, and in medicinal products such as ear and nose drops, throat lozenges, and mouthwashes.

Methyl Benzene

A.K.A

TOLUENE

• Toluene occurs naturally at low levels in crude oil

• It is usually produced in the processes of making gasoline via a catalytic reformer, in an ethylene cracker or making coke from coal.

• Final separation (either via distillation or solvent extraction) takes place in a BTX plant.

Crude Oil Coke

• Toluene, formerly known as toluol, is a clear, water-insoluble liquid with the typical smell of paint thinners.

• Chemically it is a mono-substituted benzene derivative, i.e. one in which a single hydrogen atom from the benzene molecule has been replaced by a univalent group, in this case CH3

• Toluene reacts as a normal aromatic hydrocarbon towards electrophilic aromatic substitution.

• The methyl group makes it around 25 times more reactive than benzene in such reactions.

• It undergoes smooth sulfonation to give p-toluenesulfonic acid, and chlorination by Cl2 in the presence of FeCl3 to give ortho and para isomers of chlorotoluene.

Properties of Toluene

• Molecular formula C7H8 or C6H5CH3

• Molar mass 92.14 g/mol• Appearance colorless liquid• Density 0.8669 g/mL• Melting point −93 °C• Boiling point 110.6 °C

• It undergoes nitration to give ortho and para nitrotoluene isomers, but if heated it can give dinitrotoluene and ultimately the explosive trinitrotoluene (TNT).

• Toluene is a common solvent, able to dissolve paints, paint thinners, silicone sealants, many chemical reactants, rubber, printing ink, adhesives (glues), lacquers, leather tanners, and disinfectants.

Uses of Toluene

• It can also be used as a fullerene indicator, and is a raw material for toluene diisocyanate (used in the manufacture of polyurethane foam) and TNT

• It is also used as a cement for fine polystyrene kits (by dissolving and then fusing surfaces) as it can be applied very precisely by brush and contains none of the bulk of an adhesive.

• Toluene can be used as an octane booster in gasoline fuels used in internal combustion engines

• Toluene at 86% by volume fueled all the turbo Formula 1 teams in the 1980s, first pioneered by the Honda team

• Toluene has also been used as a coolant for its good heat transfer capabilities in sodium cold traps used in nuclear reactor system loops.

• Benzoic acid, C7H6O2 is a colorless crystalline solid and the simplest aromatic carboxylic acid.

• The name derived from gum benzoin, which was for a long time the only source for benzoic acid.

Benzoic Acid

Properties of Benzoic Acid

• produced commercially by partial oxidation of toluene with oxygen.

• catalyzed by cobalt or manganese naphthenates.

• The process uses cheap raw materials, proceeds in high yield, and is considered environmentally green

• Benzoic acid is cheap and readily available• practiced for its pedagogical value. It is a common

undergraduate preparation.

• Molecular formula C6H5COOH• Molar mass 122.12 g/mol• Appearance colorless crystalline solid• Density 1.32 g/cm3, solid• Melting point 122.4 °C • Boiling point 249.2 °C

Uses of Benzoic Acid

• Feedstock: Benzoic acid is used to make a large number of chemicals. For example Benzoyl chloride, C6H5C(O)Cl, is obtained by treatment of benzoic with thionyl chloride, phosgene or one of the chlorides of phosphorus.

.

• Food preservative: Benzoic acid and its salts are used as a food preservative.

i. Benzoic acid inhibits the growth of mold, yeast and some bacteria

ii. created from reactions with its sodium, potassium, or calcium salt.

• Medicinal: a constituent of Whitfield‘s Ointment which is used for the treatment of fungal skin diseases such as tinea, ringworm, and athlete's foot.

THE END