Thio
Encyclopedia
The prefix thio-, when applied to a chemical, such as an ion
, means that an oxygen
atom in the compound has been replaced by a sulfur
atom. This meaning is especially valid in organic chemistry
. For example, the word ether
refers to an oxygen-containing compound having the general chemical structure
R-O-R', where R and R' are organic radicals and O is an oxygen atom. Thioether
refers to an analogous compound with the general structure R-S-R' where S is a sulfur atom covalently bonded to two organic radicals . A chemical reaction involving the replacement of oxygen to sulfur is called thionation or thiation.
Thio- can be prefixed with di- and tri- in chemical nomenclature.
The word derives from Greek
θειον = "sulfur" (which occurs in Greek epic poetry
as θειον and may come from the same root as Latin
fumus (Indo-European
dh-w) and may have originally meant "fumigation
substance".)
Ion
An ion is an atom or molecule in which the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge. The name was given by physicist Michael Faraday for the substances that allow a current to pass between electrodes in a...
, means that an oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
atom in the compound has been replaced by a sulfur
Sulfur
Sulfur or sulphur is the chemical element with atomic number 16. In the periodic table it is represented by the symbol S. It is an abundant, multivalent non-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S8. Elemental sulfur is a bright yellow...
atom. This meaning is especially valid in organic chemistry
Organic chemistry
Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, composition, reactions, and preparation of carbon-based compounds, hydrocarbons, and their derivatives...
. For example, the word ether
Ether
Ethers are a class of organic compounds that contain an ether group — an oxygen atom connected to two alkyl or aryl groups — of general formula R–O–R'. A typical example is the solvent and anesthetic diethyl ether, commonly referred to simply as "ether"...
refers to an oxygen-containing compound having the general chemical structure
Chemical structure
A chemical structure includes molecular geometry, electronic structure and crystal structure of molecules. Molecular geometry refers to the spatial arrangement of atoms in a molecule and the chemical bonds that hold the atoms together. Molecular geometry can range from the very simple, such as...
R-O-R', where R and R' are organic radicals and O is an oxygen atom. Thioether
Thioether
A thioether is a functional group in organosulfur chemistry with the connectivity C-S-C as shown on right. Like many other sulfur-containing compounds, volatile thioethers have foul odors. A thioether is similar to an ether except that it contains a sulfur atom in place of the oxygen...
refers to an analogous compound with the general structure R-S-R' where S is a sulfur atom covalently bonded to two organic radicals . A chemical reaction involving the replacement of oxygen to sulfur is called thionation or thiation.
Thio- can be prefixed with di- and tri- in chemical nomenclature.
The word derives from Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
θειον = "sulfur" (which occurs in Greek epic poetry
Epic poetry
An epic is a lengthy narrative poem, ordinarily concerning a serious subject containing details of heroic deeds and events significant to a culture or nation. Oral poetry may qualify as an epic, and Albert Lord and Milman Parry have argued that classical epics were fundamentally an oral poetic form...
as θειον and may come from the same root as Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
fumus (Indo-European
Proto-Indo-European language
The Proto-Indo-European language is the reconstructed common ancestor of the Indo-European languages, spoken by the Proto-Indo-Europeans...
dh-w) and may have originally meant "fumigation
Fumigation
Fumigation is a method of pest control that completely fills an area with gaseous pesticides—or fumigants—to suffocate or poison the pests within. It is utilized for control of pests in buildings , soil, grain, and produce, and is also used during processing of goods to be imported or...
substance".)
See also
- Organosulfur compoundsOrganosulfur compoundsOrganosulfur compounds are organic compounds that contain sulfur. They are often associated with foul odours, but many of the sweetest compounds known are organosulfur derivatives. Nature abounds with organosulfur compounds—sulfur is essential for life. Two of the 20 common amino acids are...
- Seleno-
- Telluro-
- ThioamideThioamideThioamide is a functional group with the general structure R-CS-NR'R, where R, R', and R are organic groups. They are analogous to amides but they exhibit greater multiple bond character along the C-N bond, resulting in a larger rotational barrier...
- ThiocyanateThiocyanateThiocyanate is the anion [SCN]−. It is the conjugate base of thiocyanic acid. Common derivatives include the colourless salts potassium thiocyanate and sodium thiocyanate. Organic compounds containing the functional group SCN are also called thiocyanates...
- ThioetherThioetherA thioether is a functional group in organosulfur chemistry with the connectivity C-S-C as shown on right. Like many other sulfur-containing compounds, volatile thioethers have foul odors. A thioether is similar to an ether except that it contains a sulfur atom in place of the oxygen...
- ThioketoneThioketoneThioketones are organosulfur compounds related to conventional ketones. Instead of the formula R2C=O, thioketones have the formula R2C=S. Unhindered alkylthioketones are typically unstable; such compounds tend to form polymers or rings.-Preparative methods:Thiones are usually prepared from ketones...
- ThiolThiolIn organic chemistry, a thiol is an organosulfur compound that contains a carbon-bonded sulfhydryl group...
- ThiopheneThiopheneThiophene is a heterocyclic compound with the formula C4H4S. Consisting of a flat five-membered ring, it is aromatic as indicated by its extensive substitution reactions. Related to thiophene are benzothiophene and dibenzothiophene, containing the thiophene ring fused with one and two benzene...
- ThioureaThioureaThiourea is an organosulfur compound of with the formula SC2 . It is structurally similar to urea, except that the oxygen atom is replaced by a sulfur atom, but the properties of urea and thiourea differ significantly. Thiourea is a reagent in organic synthesis. "Thioureas" refers to a broad...
- ThiosulfateThiosulfateThiosulfate is an oxyanion of sulfur. The prefix thio indicates that thiosulfate ion is a sulfate ion with one oxygen replaced by a sulfur. Thiosulfate occurs naturally and is produced by certain biochemical processes...
- IUPAC nomenclature of organic chemistryIUPAC nomenclature of organic chemistryThe IUPAC nomenclature of organic chemistry is a systematic method of naming organic chemical compounds as recommended by the International Union of Pure and Applied Chemistry . Ideally, every possible organic compound should have a name from which an unambiguous structural formula can be drawn. ...