ORGANIC CHEMISTRY

ORGANIC CHEMISTRY

Is the chemistry of the compoundsof carbon.

Chemistry of compounds thatcontains the element of carbon.

Organic compounds were thoseobtained from plant or animalsources, that is from materialproduced by living organisms.

HISTORYOrganic chemistry is the area of chemistry thatinvolves the study of carbon and its compounds

(Oparin, 1923) In theory organic chemistry mayhave its beginnings with the big bang when thecomponents of ammonia, nitrogen, carbon dioxideand methane combined to form amino acids, anexperiment that has been verified in the laboratory(Miller, 1950)

In the 16th century organic compounds were isolated from nature in the pure state (Scheele, 1769) and analytical methods were developed for determination of elemental composition (Lavoisier, 1784).

Frederich Wöhler (1828) discovered that urea, a natural component in urine, could be synthesized in the laboratory by heating ammonium cyanate.

By the middle of the nineteenth century manyadvances had been made into the discovery,analysis and synthesis of many new organiccompounds. Understanding about the structuresof organic chemistry began with a theory ofbonding called valence theory (Kekule, Couper,1858).

Organic chemistry is a field of immense importance to technology.

Organic chemistry is fundamental to biology and medicine.

Living organisms are made up of organic compounds; the molecules of “molecular biology” are organic molecules.

Biology, on molecular level is Organic Chemistry.

We are now living in the Age of Carbon.

Every day the newspapers bring to our attentioncompounds of carbon.

Wars are fought over petroleum.

Twin catastrophes threaten us both arising from theaccumulation in the atmosphere of compounds ofcarbon.

1990 the journal Science selected as the molecules ofthe year of diamond, one of the allotropic form ofcarbon.

Organic compound could be made by living cell or organs.(present in living organism).

The word “organic” is still used today by some people to mean “coming from living organisms”

The commonly used term “organic food” means that the food was grown without the use of synthetic fertilizers and pesticides.

THE CHEmISTry Of...Natural Products

An “organic vitamin” means to these people that the vitamin was isolated from a natural source and not synthesized by a chemist.

It is impossible to argue that pure “natural” vitamin c, for example, is healthier than pure “synthetic” vitamin c, since the two sub- stances are identical in all respects.

In science today, the study of compounds from living organisms is called natural products chemistry.

Organic compounds, in general, differ greatly from

inorganic compounds in seven respects:

Properties of Organic Compounds

Organic compounds are usually less soluble in water.

Organic compoundsare usuallycombustible.

Organic compounds, ingeneral, have lowermelting and boilingpoints.

Several organic compounds may existfor a given formula. This is known asisomerism

Reactions of organic compounds are usually

molecular rather than ionic. As a result, they

are often quite slow.

Organic are form covalent leakage

The molecular weights of organic compounds

may be very high, often well over 1000.

Most organic compounds can serve as a source

of food for bacteria.

Comparison of organic and inOrganic Compounds

Organic are form covalent leakage while

inorganic are joined with electrovalent or ionic

compounds.

Organic burn readily, some spontaneously togive CO2 ,H2O and in some cases other produces

inorganic incombustible compounds

Organic are less soluble in water, but more

soluble in organic liquids like alcohol, ether,

chloroform and benzene.

Organic are less stable towards heat.

Organic are less reactive than in organic.

Sources of Organic CompoundsOrganic compounds are derived from three sources:

Nature: fibers, vegetable oils, animal oils and fats,

alkaloids, cellulose, starch, sugars, and so on.

Synthesis: A wide variety of compounds and

materials prepared by manufacturing processes.

Fermentation: Alcohols, acetone, glycerol,

antibiotics, acids, and the like are derived by the

action of microorganisms upon organic matter.

The wastes produced in the processing of

natural organic materials and from the synthetic

organic and fermentation industries constitute a

major part of the industrial and hazardous

waste problems that environmental engineers

and scientists are called upon to solve.

PETROLEUM AND COALBoth of these are organic.

Two large reservoirs of organic materials.

Products of the decay of plants and animals.

We recognize these as the fossil fuels – non renewable.

Petroleum are being consumed at an alarming rate to meet our constantly increasing demands for power.

Less than 10% of it used goes into making chemicals and most of it simply burned to supply

Types of Organic CompoundsNatural Organic Compound – refer to those

produced by plants and animals. Many of these

compounds are still extracted from natural sources

because they would be far too expensive to

produced artificially.

Synthetic Organic Compounds – are

produced in the laboratories.These chemicals that do not occur naturally.

Types of organic formula

CARBONIs one of the most interesting elements, because its compound are present in all living things.

The number of compounds that contain carbon is many times greater than the number of compounds that do not contain carbon.

Carbon atoms can attached themselves to one another to an extent not possible for atoms of any other element.

Carbon atoms can form chains thousands of atoms long, or rings of all sizes; the chains and rings can have branches and cross-links.

To the carbon atoms of these chains and rings there are attached other atoms, chiefly hydrogen, but also fluorine, chlorine, bromine, iodine, oxygen, nitrogen, sulfur, phosphorus and many others.

Each different arrangement of atoms corresponds to a different compound, and each compound has its own characteristic set of chemical properties.

How is it possible to have so manycompounds of carbon?

There are two reasons.

In the first place, carbon normally hasfour covalent bonds (four electrons toshare).

Most important reason is concernedwith the ability of carbon atoms tolink together by covalent bonding ina wide variety of ways like chains andring s molecules

What are the other elements consideredas organic compounds?C, H, O, N, S, P and halogens andsometimes the metals are elementsconsidered as organic compounds.Number of organic compounds aremore than 1 million.10 to 20 times the number of inorganiccompounds.

Structural formulas of carbon

Continuous open chain

chain with branches

in a ring

in chains or rings containing other elements

isomerismIn inorganic chemistry, a molecular formula is specific for one compound.

In organic chemistry, most molecular formulas do not represent any particular compound.

For example, the molecular formulaC3H6O3 represents at least four separatecompounds:

Compounds having the same molecularformula are known as isomers.

The term structural formulas is appliedto molecular representations as drawnfor the four compounds.

may be written as;

CLASSIFICATIONS OF ORGANIC COMPOUNDS

Organic compounds are oftenclassified according to the type (s)of functional groups present.

HYDROCARBONS Certain Organic compounds containonly two elements, Hydrogen and Carbon

They are known as Hydrocarbons.

Hydrocarbons are divided into twoclasses.

- Aliphatic hydrocarbon

- Aromatic hydrocarbon

Aliphatic hydrocarbons are divided intofamilies

Alkanes, Alkenes, Alkynes and their cyclicanalogous (cycloaliphatic)

Aliphatic compounds are those in whichthe characteristic groups are linked to astraight or branched carbon chain.

Aromaticcompounds havethese groups linked toa particular type ofsix-member carbonring that containsthree alternatingdouble bonds.