Iodosobenzene or iodosylbenzene is an
organoiodine compound
Organoiodine chemistry is the study of the synthesis and properties of organoiodine compounds, or organoiodides, organic compounds that contain one or more carbon–iodine bonds. They occur widely in organic chemistry, but are relatively rare ...
with the
empirical formula
In chemistry, the empirical formula of a chemical compound is the simplest whole number ratio of atoms present in a compound. A simple example of this concept is that the empirical formula of sulfur monoxide, or SO, is simply SO, as is the empir ...
. This colourless solid compound is used as an oxo transfer
reagent
In chemistry, a reagent ( ) or analytical reagent is a substance or compound added to a system to cause a chemical reaction, or test if one occurs. The terms ''reactant'' and ''reagent'' are often used interchangeably, but reactant specifies a ...
in research laboratories examining organic and
coordination chemistry
A coordination complex is a chemical compound consisting of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of chemical bond, bound molecules or ions, that are in turn known as ' ...
.
Preparation and structure
Iodosobenzene is prepared from
iodobenzene
Iodobenzene is an aryl iodide and the simplest of the iodobenzenes, consisting of a benzene ring substituted with one iodine atom. Its chemical formula is . It is useful as a synthetic intermediate in organic chemistry. It is a volatile colorles ...
. It is prepared by first oxidizing iodobenzene by
peracetic acid
Peracetic acid (also known as peroxyacetic acid, or Percidine) is an organic compound with the formula CH3CO3H. This peroxy acid is a colorless liquid with a characteristic acrid odor reminiscent of acetic acid. It can be highly corrosive.
Perac ...
. Hydrolysis of resulting diacetate affords "PhIO":
:
:
The structure of iodosobenzene has been verified by
crystallographically. Related derivatives are also oligomeric. Its low solubility in most solvents and
vibrational spectroscopy
Infrared spectroscopy (IR spectroscopy or vibrational spectroscopy) is the measurement of the interaction of infrared radiation with matter by absorption, emission, or reflection. It is used to study and identify chemical substances or functio ...
indicate that it is not molecular, but is polymeric, consisting of –I–O–I–O– chains. The related diacetate, , illustrates the ability of iodine(III) to adopt a T-shaped geometry without multiple bonds.
Theoretical studies show that the bonding between the iodine and oxygen atoms in iodosobenzene represents a single dative I-O sigma bond, confirming the absence of the double I=O bond.
A monomeric derivative iodosylbenzene is known in the form of 2-(tert-butylsulfonyl)iodosylbenzene, a yellow solid. C-I-O angle is 94.78°, C-I and I-O distances are 2.128 and 1.848 Å.
Applications
Iodosobenzene has no commercial uses, but in the laboratory it is employed as an "oxo-transfer reagent." It epoxidizes certain alkenes and converts some metal complexes into the corresponding oxo derivatives. Although it is an oxidant, it is also mildly nucleophilic. These oxo-transfer reactions operate by the intermediacy of adducts PhI=O→M, which release PhI.
A mixture of iodosobenzene and
sodium azide
Sodium azide is an inorganic compound with the formula . This colorless salt is the gas-forming component in some car airbag systems. It is used for the preparation of other azide compounds. It is highly soluble in water and is acutely poisonou ...
in
acetic acid
Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main compone ...
converts alkenes to
vicinal diazides:.
:
Safety
This compound is explosive and should not be heated under vacuum.
See also
*
Dess-Martin reagent
References
{{Reflist
Iodanes
Phenyl compounds
Inorganic polymers
Reagents for organic chemistry