Iodobenzene

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Iodobenzene
Iodobenzene Iodbenzol.svg
Iodobenzene
Iodobenzene-3D-vdW.png
Names
Preferred IUPAC name
Iodobenzene
Other names
Phenyl iodide
Identifiers
3D model (JSmol)
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.008.837 OOjs UI icon edit-ltr-progressive.svg
PubChem CID
UNII
  • InChI=1S/C6H5I/c7-6-4-2-1-3-5-6/h1-5H Yes check.svgY
    Key: SNHMUERNLJLMHN-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/C6H5I/c7-6-4-2-1-3-5-6/h1-5H
    Key: SNHMUERNLJLMHN-UHFFFAOYAQ
  • c1ccc(cc1)I
Properties
C6H5I
Molar mass 204.01 g/mol
Appearancecolorless liquid
Density 1.823 g/cm3
Melting point −29 °C (−20 °F; 244 K)
Boiling point 188 °C (370 °F; 461 K)
Insoluble
log P 3
-92.00·10−6 cm3/mol
Viscosity 1.5042 mPa·s (300.65 K) [1]
Hazards
Flash point 74.44 °C (165.99 °F; 347.59 K)
Thermochemistry
0.779 J/K
Related compounds
Related halobenzenes
Fluorobenzene
Chlorobenzene
Bromobenzene
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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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 C6H5I. It is useful as a synthetic intermediate in organic chemistry. It is a volatile colorless liquid, although aged samples appear yellowish.

Contents

Preparation

Iodobenzene is commercially available, or it can be prepared in the laboratory from aniline via the diazotization reaction. In the first step, the amine functional group is diazotized with hydrochloric acid and sodium nitrite. Potassium iodide is added to the resultant phenyldiazonium chloride, causing nitrogen gas to evolve. The product is separated by steam distillation. [2]

Synthesis Iodobenzene.svg

Alternatively, it can be produced by refluxing iodine and nitric acid with benzene. [3]

Reactions

Since the C–I bond is weaker than C–Br or C–Cl, iodobenzene is more reactive than bromobenzene or chlorobenzene. Iodobenzene reacts readily with magnesium to form the Grignard reagent, phenylmagnesium iodide. Phenylmagnesium iodide, like the bromide analog, is a synthetic equivalent for the phenyl anion synthon. Iodobenzene reacts with chlorine to give the complex, iodobenzene dichloride, [4] which is used as a solid source of chlorine.

Iodobenzene can also serve as a substrate for the Sonogashira coupling, Heck reaction, and other metal-catalyzed couplings. These reactions proceed via the oxidative addition of iodobenzene.

Further reading

Related Research Articles

In organic chemistry, an aryl halide is an aromatic compound in which one or more hydrogen atoms, directly bonded to an aromatic ring are replaced by a halide. The haloarene are different from haloalkanes because they exhibit many differences in methods of preparation and properties. The most important members are the aryl chlorides, but the class of compounds is so broad that there are many derivatives and applications.

<span class="mw-page-title-main">Thionyl chloride</span> Inorganic compound (SOCl2)

Thionyl chloride is an inorganic compound with the chemical formula SOCl2. It is a moderately volatile, colourless liquid with an unpleasant acrid odour. Thionyl chloride is primarily used as a chlorinating reagent, with approximately 45,000 tonnes per year being produced during the early 1990s, but is occasionally also used as a solvent. It is toxic, reacts with water, and is also listed under the Chemical Weapons Convention as it may be used for the production of chemical weapons.

<span class="mw-page-title-main">Phosphorus pentachloride</span> Chemical compound

Phosphorus pentachloride is the chemical compound with the formula PCl5. It is one of the most important phosphorus chlorides/oxychlorides, others being PCl3 and POCl3. PCl5 finds use as a chlorinating reagent. It is a colourless, water-sensitive solid, although commercial samples can be yellowish and contaminated with hydrogen chloride.

In organic chemistry, an azo coupling is an organic reaction between a diazonium compound and another aromatic compound that produces an azo compound. In this electrophilic aromatic substitution reaction, the aryldiazonium cation is the electrophile and the activated carbon act as a nucleophile. In most cases, including the examples below, the diazonium compound is also aromatic.

A pinacol coupling reaction is an organic reaction in which a carbon–carbon bond is formed between the carbonyl groups of an aldehyde or a ketone in presence of an electron donor in a free radical process. The reaction product is a vicinal diol. The reaction is named after pinacol, which is the product of this reaction when done with acetone as reagent. The reaction is usually a homocoupling but intramolecular cross-coupling reactions are also possible. Pinacol was discovered by Wilhelm Rudolph Fittig in 1859.

<span class="mw-page-title-main">Thiophenol</span> Chemical compound

Thiophenol is an organosulfur compound with the formula C6H5SH, sometimes abbreviated as PhSH. This foul-smelling colorless liquid is the simplest aromatic thiol. The chemical structures of thiophenol and its derivatives are analogous to phenols. An exception is the oxygen atom in the hydroxyl group (-OH) bonded to the aromatic ring is replaced by a sulfur atom. The prefix thio- implies a sulfur-containing compound and when used before a root word name for a compound which would normally contain an oxygen atom, in the case of 'thiol' that the alcohol oxygen atom is replaced by a sulfur atom.

<span class="mw-page-title-main">Sulfur dichloride</span> Chemical compound

Sulfur dichloride is the chemical compound with the formula SCl2. This cherry-red liquid is the simplest sulfur chloride and one of the most common, and it is used as a precursor to organosulfur compounds. It is a highly corrosive and toxic substance, and it reacts on contact with water to form chlorine-containing acids.

Benzyl chloride, or α-chlorotoluene, is an organic compound with the formula C6H5CH2Cl. This colorless liquid is a reactive organochlorine compound that is a widely used chemical building block.

<span class="mw-page-title-main">(Bis(trifluoroacetoxy)iodo)benzene</span> Chemical compound

(Bis iodo)benzene, C
6
H
5
I(OCOCF
3
)
2
, is a hypervalent iodine compound used as a reagent in organic chemistry. It can be used to carry out the Hofmann rearrangement under acidic conditions.

<span class="mw-page-title-main">Disulfur dichloride</span> Chemical compound

Disulfur dichloride is the inorganic compound of sulfur and chlorine with the formula S2Cl2. It is an amber oily liquid.

<span class="mw-page-title-main">Organomercury chemistry</span> Group of chemical compounds containing mercury

Organomercury chemistry refers to the study of organometallic compounds that contain mercury. Typically the Hg–C bond is stable toward air and moisture but sensitive to light. Important organomercury compounds are the methylmercury(II) cation, CH3Hg+; ethylmercury(II) cation, C2H5Hg+; dimethylmercury, (CH3)2Hg, diethylmercury and merbromin ("Mercurochrome"). Thiomersal is used as a preservative for vaccines and intravenous drugs.

<span class="mw-page-title-main">Iodine monochloride</span> Chemical compound

Iodine monochloride is an interhalogen compound with the formula ICl. It is a red-brown chemical compound that melts near room temperature. Because of the difference in the electronegativity of iodine and chlorine, this molecule is highly polar and behaves as a source of I+. Discovered in 1814 by Gay-Lussac, iodine monochloride is the first interhalogen compound discovered.

Iodine compounds are compounds containing the element iodine. Iodine can form compounds using multiple oxidation states. Iodine is quite reactive, but it is much less reactive than the other halogens. For example, while chlorine gas will halogenate carbon monoxide, nitric oxide, and sulfur dioxide, iodine will not do so. Furthermore, iodination of metals tends to result in lower oxidation states than chlorination or bromination; for example, rhenium metal reacts with chlorine to form rhenium hexachloride, but with bromine it forms only rhenium pentabromide and iodine can achieve only rhenium tetraiodide. By the same token, however, since iodine has the lowest ionisation energy among the halogens and is the most easily oxidised of them, it has a more significant cationic chemistry and its higher oxidation states are rather more stable than those of bromine and chlorine, for example in iodine heptafluoride.

In inorganic chemistry, sulfonyl halide groups occur when a sulfonyl functional group is singly bonded to a halogen atom. They have the general formula RSO2X, where X is a halogen. The stability of sulfonyl halides decreases in the order fluorides > chlorides > bromides > iodides, all four types being well known. The sulfonyl chlorides and fluorides are of dominant importance in this series.

<span class="mw-page-title-main">Phenylmagnesium bromide</span> Chemical compound

Phenylmagnesium bromide, with the simplified formula C
6
H
5
MgBr
, is a magnesium-containing organometallic compound. It is commercially available as a solution in diethyl ether or tetrahydrofuran (THF). Phenylmagnesium bromide is a Grignard reagent. It is often used as a synthetic equivalent for the phenyl "Ph" synthon.

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 in nature. The thyroxine hormones are organoiodine compounds that are required for health and the reason for government-mandated iodization of salt.

Unlike its lighter congeners, the halogen iodine forms a number of stable organic compounds, in which iodine exhibits higher formal oxidation states than -1 or coordination number exceeding 1. These are the hypervalent organoiodines, often called iodanes after the IUPAC rule used to name them.

Iodobenzene dichloride (PhICl2) is a complex of iodobenzene with chlorine. As a reagent for organic chemistry, it is used as an oxidant and chlorinating agent.

<span class="mw-page-title-main">(Diacetoxyiodo)benzene</span> Chemical compound

(Diacetoxyiodo)benzene, also known as phenyliodine(III) diacetate (PIDA) is a hypervalent iodine chemical with the formula C
6
H
5
I(OCOCH
3
)
2
. It is used as an oxidizing agent in organic chemistry.

<span class="mw-page-title-main">1-Bromo-4-iodobenzene</span> Chemical compound

1-Bromo-4-iodobenzene is a mixed aryl halide (aryl bromide and aryl iodide) with the formula BrC6H4I.

References

  1. Viswanath, D.S.; Natarajan, G. (1989), Data Book on the Viscosity of Liquids, Hemisphere Publishing, ISBN   0-89116-778-1
  2. H. J. Lucas, E. R. Kennedy (1939). "Iodobenzene". Organic Syntheses .; Collective Volume, vol. 2, p. 351
  3. F. B. Dains and R. Q. Brewster (1941). "Iodobenzene". Organic Syntheses .; Collective Volume, vol. 1, p. 323
  4. H. J. Lucas and E. R. Kennedy. "Iodobenzene dichloride". Organic Syntheses .; Collective Volume, vol. 3, p. 482