Cyclohexanehexathione is a cyclic
covalent compound
A covalent bond is a chemical bond that involves the sharing of electrons to form electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs. The stable balance of attractive and repulsive forces between atom ...
consisting of a six-
carbon
Carbon () is a chemical element; it has chemical symbol, symbol C and atomic number 6. It is nonmetallic and tetravalence, tetravalent—meaning that its atoms are able to form up to four covalent bonds due to its valence shell exhibiting 4 ...
ring with a
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 ...
bonded to each. It has been generated by neutralization of its mono
anion
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 conven ...
() in a
mass spectrometer
Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a '' mass spectrum'', a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is us ...
. This compound is the
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known as thiones or thiocarbonyls) are organosulfur compounds related to conventional ketones in which the oxygen has been replaced by a sulfur.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 ...
analog of
cyclohexanehexone
Cyclohexanehexone, also known as hexaketocyclohexane and triquinoyl, is an organic compound with formula , the sixfold ketone of cyclohexane. It is an oxide of carbon (an oxocarbon), a hexamer of carbon monoxide.
The compound is expected to be hi ...
; that oxygen variant is expected to be substantially less stable.
Synthesis of by
photolysis
Photodissociation, photolysis, photodecomposition, or photofragmentation is a chemical reaction in which molecules of a chemical compound are broken down by absorption of light or photons. It is defined as the interaction of one or more photons wi ...
or
pyrolysis
Pyrolysis is a process involving the Bond cleavage, separation of covalent bonds in organic matter by thermal decomposition within an Chemically inert, inert environment without oxygen. Etymology
The word ''pyrolysis'' is coined from the Gree ...
to extrude three equivalents of
carbon monoxide
Carbon monoxide (chemical formula CO) is a poisonous, flammable gas that is colorless, odorless, tasteless, and slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the si ...
from a precursor containing adjacent pairs of sulfurs as cyclic
dithiocarbonate Thiocarbonate describes a family of anions with the general chemical formula (''x'' = 0, 1, or 2):
*for ''x'' = 2 it is monothiocarbonate ion
*for ''x'' = 1 it is dithiocarbonate ion
*for ''x'' = 0 it is trithiocarbonate ion
Like the carbonate d ...
units gave what is more likely a different
valence isomer
In organic chemistry, two molecules are valence isomers when they are constitutional isomers that can interconvert through pericyclic reactions.
Benzene
There are many valence isomers one can draw for the C6H6 formula benzene. Some were original ...
, as various
dithiete
Dithiete is an unsaturated heterocyclic compound that contains two adjacent sulfur atoms and two sp2-hybridized carbon centers. Derivatives are known collectively as dithietes or 1,2-dithietes. With 6 π electrons, 1,2-dithietes are examples of ...
-containing structures are predicted to be more stable than the hexathione form.
:
This theoretical analysis of the various isomers and experimental analysis of this reaction cast doubt on whether the mass spectrometric approach really did produce the hexathione isomer as originally claimed. The increased stability of dithietes as compared to
dioxetane
A dioxetane or dioxacyclobutane is an organic compound with formula C2O2H4, whose backbone is a four-membered ring of two oxygen atoms and two carbon atoms. There are two isomers:
* 1,2-dioxetane where the oxygen atoms are adjacent.
* 1,3-dioxetane ...
-like rings is one of theoretical bases for proposing is more stable than the oxygen analog.
References
{{inorganic-compound-stub
Inorganic carbon compounds
Inorganic sulfur compounds
Thioketones