Iodobenzene 5120016 221624353 2008-06-25T10:05:04Z Arakin 142650 +ja {{Chembox new | Name = Iodobenzene | ImageFileL1 = Iodobenzene.gif | ImageSizeL1 = 100px | ImageNameL1 = Iodobenzene | ImageFileR1 = Iodobenzene-3D-vdW.png | ImageSizeR1 = 120px | ImageName1 = Space-filling model of iodobenzene | IUPACName = Iodobenzene | Section1 = {{Chembox Identifiers | CASNo = 591-50-4 | SMILES = Ic1ccccc1 }} | Section2 = {{Chembox Properties | Formula = C<sub>6</sub>H<sub>5</sub>I | MolarMass = 204.01 g/mol | Density = 1.831 g/cm<sup>3</sup> | MeltingPt = -29 °C | BoilingPt = 188 °C }} }} '''Iodobenzene''' is an [[organic compound]] consisting of a [[benzene]] ring substitituted with one [[iodine]] atom. It is useful as a synthetic intermediate in [[organic chemistry]]. Since the C-I bond is weaker than C-Br or C-Cl, it is more reactive than [[bromobenzene]] or [[chlorobenzene]]. Iodobenzene can react with [[magnesium]] to form a [[Grignard reagent]], phenylmagnesium iodide. Phenylmagnesium iodide, like the [[phenylmagnesium bromide|bromide]] analog, is a synthetic equivalent for the [[phenyl]] anion [[synthon]]. It can also serve as a [[substrate]] for the [[Sonogashira coupling]], [[Heck reaction]], and other metal-catalyzed couplings. ==Preparation== Iodobenzene is commercially available, but it may be prepared in the laboratory from [[aniline]]. In the first step, the [[amine]] functional group is [[diazonium salt|diazotized]] with [[hydrochloric acid]] and [[sodium nitrite]]. [[Potassium iodide]] is added to the resultant diazonium chloride, causing [[nitrogen]] gas to evolve. Any excess nitrite is hydrolyzed with a strong base; the mixture is acidified and the desired product is separated by steam distillation.<ref>{{OrgSynth | author = H. J. Lucas, E. R. Kennedy | title = Iodobenzene | year= 1939 | collvol = 2 | collvolpages = 351 | prep = cv2p0351 }} </ref> Alternatively, it may be produced by refluxing [[iodine]] and [[nitric acid]] with benzene. <ref>{{OrgSynth | author = F. B. Dains and R. Q. Brewster | title = Iodobenzene | year= 1941 | collvol = 1 | collvolpages = 323 | prep = cv1p323 }} </ref> ==References== <references/> ==See also== *Gattermann-Wieland, "Laboratory Methods of Organic Chemistry," p. 283. Translated from the twenty-fourth German edition by W. McCartney, The Macmillan Company, New York, 1937. [[Category:Aromatic compounds]] [[Category:Organoiodides]] [[ja:ヨードベンゼン]]