The
prefix
A prefix is an affix which is placed before the stem of a word. Adding it to the beginning of one word changes it into another word. For example, when the prefix ''un-'' is added to the word ''happy'', it creates the word ''unhappy''. Particula ...
thio-, when applied to a chemical, such as an
ion
An ion () is an atom or molecule with a net electrical charge.
The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by conv ...
, means that an
oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as ...
atom in the compound has been replaced by a
sulfur
Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formul ...
atom. This term is often used in
organic chemistry
Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, and reactions of organic compounds and organic materials, i.e., matter in its various forms that contain carbon atoms.Clayden, J. ...
. For example, from the word ''
ether
In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again b ...
,'' referring to an oxygen-containing compound having the general
chemical structure
A chemical structure determination includes a chemist's specifying the molecular geometry and, when feasible and necessary, the electronic structure of the target molecule or other solid. Molecular geometry refers to the spatial arrangement of a ...
, where R and R′ are organic
functional groups
In organic chemistry, a functional group is a substituent or moiety in a molecule that causes the molecule's characteristic chemical reactions. The same functional group will undergo the same or similar chemical reactions regardless of the res ...
and O is an oxygen atom, comes the word ''
thioether
In organic chemistry, an organic sulfide (British English sulphide) or thioether is an organosulfur functional group with the connectivity as shown on right. Like many other sulfur-containing compounds, volatile sulfides have foul odors. A sul ...
'', which refers to an analogous compound with the general structure , where S is a sulfur atom covalently bonded to two organic groups.
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 (which occurs in Greek
epic poetry
An epic poem, or simply an epic, is a lengthy narrative poem typically about the extraordinary deeds of extraordinary characters who, in dealings with gods or other superhuman forces, gave shape to the mortal universe for their descendants.
...
as grc, θέ(ϝ)ειον, théweion, label=none and may come from the same root as
Latin
Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through ...
(
Indo-European
The Indo-European languages are a language family native to the overwhelming majority of Europe, the Iranian plateau, and the northern Indian subcontinent. Some European languages of this family, English, French, Portuguese, Russian, Dutc ...
''dh-w'') and may have originally meant "
fumigation
Fumigation is a method of pest control or the removal of harmful micro-organisms by completely filling an area with gaseous pesticides—or fumigants—to suffocate or poison the pests within. It is used to control pests in buildings (s ...
substance".)
Examples
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Thioamide
A thioamide (rarely, thionamide, but also known as thiourylenes) 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 ch ...
*
Thiocyanate
Thiocyanate (also known as rhodanide) is the anion . It is the conjugate base of thiocyanic acid. Common derivatives include the colourless salts potassium thiocyanate and sodium thiocyanate. Mercury(II) thiocyanate was formerly used in ...
*
Thioether
In organic chemistry, an organic sulfide (British English sulphide) or thioether is an organosulfur functional group with the connectivity as shown on right. Like many other sulfur-containing compounds, volatile sulfides have foul odors. A sul ...
*
Thioketone
In organic chemistry, thioketones (; also known as thiones or thiocarbonyls) are organosulfur compounds related to conventional ketones in which the oxygen has been replaced by a sulfur. Instead of a structure of , thioketones have the structure ...
*
Thiol
In organic chemistry, a thiol (; ), or thiol derivative, is any organosulfur compound of the form , where R represents an alkyl or other organic substituent. The functional group itself is referred to as either a thiol group or a sulfhydryl grou ...
*
Thiophene
Thiophene is a heterocyclic compound with the formula C4H4S. Consisting of a planar five-membered ring, it is aromatic as indicated by its extensive substitution reactions. It is a colorless liquid with a benzene-like odor. In most of its reacti ...
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Thiourea
Thiourea () is an organosulfur compound with the formula and the structure . It is structurally similar to urea (), except that the oxygen atom is replaced by a sulfur atom (as implied by the ''thio-'' prefix); however, the properties of ur ...
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Thiosulfate
Thiosulfate ( IUPAC-recommended spelling; sometimes thiosulphate in British English) is an oxyanion of sulfur with the chemical formula . Thiosulfate also refers to the compounds containing this anion, which are the salts of thiosulfuric acid, ...
See also
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Organosulfur compounds
Organosulfur compounds are organic compounds that contain sulfur. They are often associated with foul odors, but many of the sweetest compounds known are organosulfur derivatives, e.g., saccharin. Nature abounds with organosulfur compounds—sulfur ...
*
IUPAC nomenclature of organic chemistry
In chemical nomenclature, the IUPAC nomenclature of organic chemistry is a method of naming organic chemical compounds as recommended by the International Union of Pure and Applied Chemistry (IUPAC). It is published in the '' Nomenclature of O ...
References
{{Orgchemsuffixes
Chemistry prefixes
Prefixes