Organic chemistry

Organic chemistry is a branch of chemistry focused on the scientific study of carbon-containing compounds and materials. Its work involves determining the structural formulas of organic substances, analyzing their physical and chemical properties, and assessing their chemical reactivity to explain how they behave. The field also covers the chemical synthesis of natural products, drugs, and polymers, along with the study of individual organic molecules both in the lab and through theoretical computer-based methods.

The chemicals studied include hydrocarbons—compounds made only of carbon and hydrogen—as well as carbon-based compounds that also contain elements like oxygen, nitrogen, sulfur, phosphorus (common in biochemicals), and the halogens. A related area, organometallic chemistry, examines compounds with carbon–metal bonds. Organic compounds are the foundation of all known life and make up most known chemicals. Because carbon can form single, double, and triple bonds, as well as structures with delocalized electrons, these compounds are structurally diverse and have a vast range of uses. They are the basis of many commercial products, such as pharmaceuticals, petrochemicals, agrichemicals, lubricants, solvents, plastics, fuels, and explosives. The study of organic chemistry overlaps with organometallic chemistry, biochemistry, medicinal chemistry, polymer chemistry, and materials science.

**Educational aspects** Organic chemistry is usually taught at the college or university level. It is considered a very challenging course, though efforts have made it more accessible to students.

**History** Before the 18th century, chemists generally thought compounds from living organisms contained a "vital force" that set them apart from inorganic compounds. This idea was called vitalism. In the early 1800s, systematic studies of organic compounds began. Around 1816, Michel Chevreul studied soaps made from fats and alkalis, separating the acids that formed the soap. He showed that chemical changes could be made to fats—traditionally from organic sources—without any vital force. In 1828, Friedrich Wöhler synthesized urea (a component of urine) from inorganic salts (potassium cyanate and ammonium sulfate) in what is now called the Wöhler synthesis. Though Wöhler himself was cautious, this was the first time an organic substance was made in the lab without biological starting materials, and it is now seen as disproving vitalism. After Wöhler, Justus von Liebig helped organize organic chemistry and is considered one of its main founders. In 1856, William Henry Perkin accidentally created the organic dye Perkin's mauve while trying to make quinine; its financial success sparked widespread interest in the field. A key breakthrough came in 1858, when Friedrich August Kekulé and Archibald Scott Couper independently proposed the concept of chemical structure. They suggested that tetravalent carbon atoms could link together to form a carbon lattice, and that patterns of atomic bonding could be deduced from chemical reactions. The pharmaceutical industry began in the 1890s when Bayer first manufactured acetylsalicylic acid (aspirin). By 1910, Paul Ehrlich and his team developed arsenic-based arsphenamine (Salvarsan) as the first effective treatment for syphilis, launching the practice of chemotherapy. Ehrlich promoted the ideas of "magic bullet" drugs and systematic drug improvement, and his lab also contributed to developing antiserum for diphtheria and standardizing therapeutic serums. Early organic reactions and applications often came from luck and unexpected observations, but the latter half of the 19th century saw more systematic studies. The development of synthetic indigo is an example: Adolf von Baeyer's synthetic methods caused indigo production from plants to drop from 19,000 tons in 1897 to 1,000 tons by 1914; by 2002, 17,000 tons of synthetic indigo were made from petrochemicals. In the early 20th century, polymers and enzymes were recognized as large organic molecules, and petroleum was shown to have a biological origin. The total synthesis of complex organic compounds—like glucose, terpineol, cholesterol-related compounds, and later lysergic acid and vitamin B12—grew in complexity, enabling the creation of human hormones and their derivatives. The discovery of petroleum and the rise of the petrochemical industry further advanced organic chemistry.