Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, composition, reactions, and preparation (by synthesis or by other means) of carbon-based compounds, hydrocarbons, and their derivatives. These compounds may contain any number of other elements, including hydrogen, nitrogen, oxygen, the halogens as well as phosphorus, silicon, and sulfur.[1][2][3]
Organic compounds
are structurally diverse. The range of application of organic compounds
is enormous. They either form the basis of, or are important
constituents of, many products including plastics, drugs, petrochemicals, food, explosives, and paints. They form the basis of almost all earthly life processes (with very few exceptions).
Structure of the methane molecule: the simplest hydrocarbon compound.
History:
Main article: History of chemistry
Before the nineteenth century, chemists generally believed that
compounds obtained from living organisms were too complex to be
synthesized. According to the concept of vitalism,
organic matter was endowed with a "vital force". They named these
compounds "organic" and directed their investigations toward inorganic
materials that seemed more easily studied.
During the first half of the nineteenth century, scientists realized
that organic compounds can be synthesized in the laboratory. Around 1816
Michel Chevreul started a study of soaps made from various fats and alkalis.
He separated the different acids that, in combination with the alkali,
produced the soap. Since these were all individual compounds, he
demonstrated that it was possible to make a chemical change in various
fats (which traditionally come from organic sources), producing new
compounds, without "vital force". In 1828 Friedrich Wöhler produced the organic chemical urea (carbamide), a constituent of urine, from the inorganic ammonium cyanate NH4CNO, in what is now called the Wöhler synthesis.
Although Wöhler was always cautious about claiming that
he had
disproved the theory of vital force, this event has often been thought of as a turning point.
In 1856 William Henry Perkin, while trying to manufacture quinine, accidentally manufactured the organic dye now known as Perkin's mauve. Through its great financial success, this discovery greatly increased interest in organic chemistry.
The crucial breakthrough for organic chemistry was the concept of
chemical structure, developed independently and simultaneously by Friedrich August Kekulé and Archibald Scott Couper in 1858. Both men suggested that tetravalent
carbon atoms could link to each other to form a carbon lattice, and
that the detailed patterns of atomic bonding could be discerned by
skillful interpretations of appropriate chemical reactions.
The history of organic chemistry continued with the discovery of petroleum and its separation into fractions
according to boiling ranges. The conversion of different compound types
or individual compounds by various chemical processes created the
petroleum chemistry leading to the birth of the petrochemical industry, which successfully manufactured artificial rubbers, the various organic adhesives, the property-modifying petroleum additives, and plastics.
The pharmaceutical
industry began in the last decade of the 19th century when the
manufacturing of acetylsalicylic acid (more commonly referred to as aspirin) in Germany was started by Bayer The first time a drug was systematically improved was with arsphenamine (Salvarsan). Though numerous derivatives of the dangerous toxic atoxyl were examined by Paul Ehrlich and his group, the compound with best effectiveness and toxicity characteristics was selected for production.
Although early examples of organic reactions and applications were often serendipitous, the latter half of the 19th century witnessed highly systematic studies of organic compounds.
Beginning in the 20th century, progress of organic chemistry allowed
the synthesis of highly complex molecules via multistep procedures.
Concurrently, polymers and enzymes were understood to be large organic
molecules, and petroleum was shown to be of biological origin. The
process of finding new synthesis routes for a given compound is called
total synthesis. Total synthesis of complex natural compounds started with urea, and increased in complexity to glucose and terpineol. In 1907, total synthesis was commercialized for the first time by Gustaf Komppa with camphor Pharmaceutical benefits have been substantial. For example, cholesterol-related
compounds have opened ways to synthesis complex human hormones and
their modified derivatives. Since the start of the 20th century,
complexity of total syntheses has been increasing, with examples such as
lysergic acid and vitamin B12.
Biochemistry
has only started in the 20th century, opening up a new chapter of
organic chemistry with enormous scope. Biochemistry, like organic
chemistry, primarily focuses on compounds containing carbon.
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