Historical Development of Organic Chemistry

Study Notes

Overview of Organic Chemistry

Organic chemistry studies the structure, properties, and reactions of carbon-containing compounds.
Organic reactions are essential for synthesizing natural products, pharmaceuticals, and polymers.

Key Historical Figures and Contributions

Jons Jakob Berzelius (1779-1848)
- Explored structural isomerism in carbon compounds.
- Identified compounds like formic acid, salicylic acid, and urea.
- Proposed vitalism, suggesting that living organisms possess a vital principle beyond physical processes.
Justus von Liebig (1803-1873) & Friedrich Wohler (1800-1882)
- Pioneered modern organic chemistry in the 19th century.
- Liebig measured carbon, hydrogen, and nitrogen contents in organic compounds.
- Wohler synthesized urea from ammonium cyanate, demonstrating organic compound formation from inorganic substances.
Jean-Baptiste André Dumas (1800-1884)
- Collaborated with Liebig on radical theory.
- Developed methods for converting acetic acid to trichloroacetic acid.
Auguste Laurent (1808-1853) & Charles Frédéric Gerhardt (1816-1856)
- Proposed the type theory, emphasizing organic synthesis from simpler molecules.
- Laurent introduced homologous series, exemplified by the alkane series (methane, ethane, propane).
Hermann Kopp (1817-1892)
- Established the correlation between molecular structure and physical properties, such as boiling points linked to molecular size.
Alexander Williamson (1824-1904)
- Synthesized diethyl ether, providing insights into ether chemistry.
Edward Frankland (1825-1896)
- Developed the concept of valence, essential for understanding chemical bonding.
- Established theories of multiple valences using phosphorus trichloride and pentachloride as examples.
August Kekulé (1829-1896)
- Proposed the tetravalent nature of carbon and its ability to form chains.
- Credited for the structural model of benzene.
Archibald Scott Couper (1831-1892)
- Introduced molecular structures using dotted lines to represent bonds.
Alexander Crum Brown (1838-1922)
- Created graphical structural formulas to depict compounds.
Louis Pasteur (1822-1895), Jacobus Van’t Hoff (1852-1911), Joseph-Achille Le Bel (1847-1930)
- Explored stereoisomerism and its three-dimensional aspects, notably in tartaric acid, which displays optical activity.
Emil Fischer (1852-1919)
- Conducted studies on stereoisomers of glucose with multiple centers of asymmetry.
August Wilhelm von Hofmann (1818-1892)
- Investigated coal tar's components, isolating key aromatic hydrocarbons such as aniline, ammonia, and phenol.
William Henry Perkin (1838-1907)
- Discovered synthetic dyes, notably producing mauveine from aniline, marking a breakthrough in synthetic organic chemistry.

Important Developments in the 19th and 20th Centuries

19th Century: Focused on synthesizing new molecules and understanding natural products.
20th Century: Shifted to studying organic reactions and mechanisms, laying the groundwork for modern organic chemistry.

Categories of Discoveries in Organic Chemistry

Based on Sources
- Carbonized organic matter: gasoline, coal, natural gas.
- Living organisms: natural dyes and flavorings.
- Inventions: medicines (e.g., antibiotics), acetic acid, fertilizers.

Notable Medicinal Discoveries

Paul Ehrlich (1854-1915)
- Developed organoarsenic compounds for syphilis treatment, particularly Neosalvarsan.
Penicillin
- Initially used in 1942, became a crucial antibacterial agent.
DDT (Dichloro-Diphenyl-Trichloroethane)
- Utilized during WWII for pest control and prevention of disease spread.

Concluding Insights

The historical progression of organic chemistry greatly influenced the development of pharmaceuticals, agricultural practices, and various synthetic products.
The collaboration and competition among scientists led to key advancements that shaped modern chemistry.