A dithiane is a
heterocyclic compound
A heterocyclic compound or ring structure is a cyclic compound that has atoms of at least two different elements as members of its ring(s). Heterocyclic organic chemistry is the branch of organic chemistry dealing with the synthesis, proper ...
composed of a
cyclohexane
Cyclohexane is a cycloalkane with the molecular formula . Cyclohexane is non-polar. Cyclohexane is a colourless, flammable liquid with a distinctive detergent-like odor, reminiscent of cleaning products (in which it is sometimes used). Cyclohexan ...
core structure wherein two
methylene bridge
In chemistry, a methylene bridge is part of a molecule with formula . The carbon atom is connected by single bonds to two other distinct atoms in the rest of the molecule. A methylene bridge is often called a methylene group or simply methylene, ...
s ( units) are replaced by
sulfur
Sulfur ( American spelling and the preferred IUPAC name) or sulphur ( Commonwealth spelling) is a chemical element; it has symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms ...
. The three isomeric parent heterocycles are 1,2-dithiane, 1,3-dithiane and 1,4-dithiane. They are all colorless solids.
1,2-Dithiane
1,2-Dithiane is an
organosulfur compound
Organosulfur chemistry is the study of the properties and synthesis of organosulfur compounds, which are organic compounds that contain sulfur. They are often associated with foul odors, but many of the sweetest compounds known are organosulfur der ...
with the formula . It is one of three isomers of the formula . The 1,2-isomer, a
disulfide
In chemistry, a disulfide (or disulphide in British English) is a compound containing a functional group or the anion. The linkage is also called an SS-bond or sometimes a disulfide bridge and usually derived from two thiol groups.
In inorg ...
, arises by the oxidation of
1,4-butanedithiol.
1,3-Dithiane
1,3-Dithiane is an
organosulfur compound
Organosulfur chemistry is the study of the properties and synthesis of organosulfur compounds, which are organic compounds that contain sulfur. They are often associated with foul odors, but many of the sweetest compounds known are organosulfur der ...
with the formula . It is one of three isomers of the formula . The 1,3-isomer arises by the reaction of
1,3-propanedithiol
1,3-Propanedithiol is the chemical compound with the formula HSCH2CH2CH2SH. This dithiol is a useful reagent in organic synthesis. This liquid, which is readily available commercially, has an intense stench.
Reactions
1,3-Propanedithiol has be ...
with formaldehyde.
1,3-Dithianes are sometimes used as
protecting group
A protecting group or protective group is introduced into a molecule by chemical modification of a functional group to obtain chemoselectivity in a subsequent chemical reaction. It plays an important role in multistep organic synthesis.
In man ...
of
carbonyl
In organic chemistry, a carbonyl group is a functional group with the formula , composed of a carbon atom double bond, double-bonded to an oxygen atom, and it is divalent at the C atom. It is common to several classes of organic compounds (such a ...
-containing compounds. They form by treatment of the carbonyl compound with
1,3-propanedithiol
1,3-Propanedithiol is the chemical compound with the formula HSCH2CH2CH2SH. This dithiol is a useful reagent in organic synthesis. This liquid, which is readily available commercially, has an intense stench.
Reactions
1,3-Propanedithiol has be ...
under conditions that remove water from the system. The protecting group can be removed with mercuric reagents, a process that exploits the high affinity of Hg(II) for thiolates. 1,3-Dithianes are more importantly employed in
umpolung
In organic chemistry, umpolung () or polarity inversion is the chemical modification of a functional group with the aim of the reversal of Chemical polarity, polarity of that group. This modification allows secondary reactions of this functional g ...
reactions, such as the
Corey–Seebach reaction:
1,4-Dithiane
1,4-Dithiane is an
organosulfur compound
Organosulfur chemistry is the study of the properties and synthesis of organosulfur compounds, which are organic compounds that contain sulfur. They are often associated with foul odors, but many of the sweetest compounds known are organosulfur der ...
with the formula . It is one of three isomers of the formula . The 1,4-isomer, a bis
thioether
In organic chemistry, a 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 organic compound, volatile sulfides have ...
, arises by the alkylation of
1,2-ethanedithiol
Ethane-1,2-dithiol, also known as EDT, is a colorless liquid with the formula C H( SH). It has a very characteristic odor which is compared by many people to rotten cabbage. It is a common building block in organic synthesis and an excellent lig ...
with 1,2-dibromoethane. It has no applications but traces occur as a product of degradations, e.g., cooking coal pyrolysis.
References
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External links
Corey-Seebach Reaction