Organic compound

In chemical nomenclature, an organyl group, frequently represented by the letter R, refers to any monovalent substituent whose open valence is on a carbon atom.

[9][10] Vitalism survived for a short period after the formulation of modern ideas about the atomic theory and chemical elements.

It first came under question in 1824, when Friedrich Wöhler synthesized oxalic acid, a compound known to occur only in living organisms, from cyanogen.

The term carbogenic has been proposed by E. J. Corey as a modern alternative to organic, but this neologism remains relatively obscure.

[citation needed] As described in detail below, any definition of organic compound that uses simple, broadly-applicable criteria turns out to be unsatisfactory, to varying degrees.

), and heavier analogs thereof (e.g., cyaphide anion CP−, CSe2, COS; although carbon disulfide CS2 is often classed as an organic solvent).

Halides of carbon without hydrogen (e.g., CF4 and CClF3), phosgene (COCl2), carboranes, metal carbonyls (e.g., nickel tetracarbonyl), mellitic anhydride (C12O9), and other exotic oxocarbons are also considered inorganic by some authorities.

Neither urea CO(NH2)2 nor oxalic acid (COOH)2 are organic by this definition, yet they were two key compounds in the vitalism debate.

Other compounds lacking C-H bonds but traditionally considered organic include benzenehexol, mesoxalic acid, and carbon tetrachloride.

For example, CF4 and CCl4 would be considered by this rule to be "inorganic", whereas CHF3, CHCl3, and C2Cl6 would be organic, though these compounds share many physical and chemical properties.

[citation needed] Another distinction, based on the size of organic compounds, distinguishes between small molecules and polymers.

Examples include most sugars, some alkaloids and terpenoids, certain nutrients such as vitamin B12, and, in general, those natural products with large or stereoisometrically complicated molecules present in reasonable concentrations in living organisms.

[citation needed] Most polymers (a category that includes all plastics and rubbers) are organic synthetic or semi-synthetic compounds.