Diiodomethane or methylene iodide, commonly abbreviated "MI", is an organoiodine compound. Diiodomethane is a very dense colorless liquid; however, it decomposes upon exposure to light liberating iodine, which colours samples brownish. It is slightly soluble in water, but soluble in organic solvents. It has a very high refractive index of 1.741, and a surface tension of 0.0508 N·m−1.[3]
Because of its high density, diiodomethane is used in the determination of the density of mineral and other solid samples. It can also be used as an optical contact liquid, in conjunction with the gemmological refractometer, for determining the refractive index of certain gemstones.
Diiodomethane is a reagent for installing the CH2 group. In the Simmons–Smith reaction, it is a source of methylene.[4] In fact the Simmons–Smith reaction does not produce free carbene but proceeds via Zn-CH2I intermediates.
Diiodomethane is also a source of the equivalent of CH2+2. The synthesis of Fe2(CH2)(CO)8 illustrates this reactivity:[5]
^"methylene iodide - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 26 March 2005. Identification ad Related Records. Retrieved 27 February 2012.
^Two cyclopropanation reactions: Smith, R. D.; Simmons, H. E. "Norcarane". Organic Syntheses; Collected Volumes, vol. 5, p. 855., Ito, Y.; Fujii, S.; Nakatuska, M.; Kawamoto, F.; Saegusa, T. (1988). "One-Carbon Ring Expansion Of Cycloalkanones To Conjugated Cycloalkenones: 2-Cyclohepten-1-one". Organic Syntheses; Collected Volumes, vol. 6, p. 327.
^Sumner, Charles E.; Riley, Paul E.; Davis, Raymond E.; Pettit, R. (1980). "Synthesis, Crystal Structure, and Chemical Reactivity of Octacarbonyl-μ-methylene-diiron". Journal of the American Chemical Society. 102 (5): 1752–1754. doi:10.1021/ja00525a062.
^ abRoger Adams; C. S. Marvel (1921). "Methylene Iodide". Organic Syntheses. 1: 57. doi:10.15227/orgsyn.001.0057.
^Miller, William Allen (1880). Elements of Chemistry: Chemistry of carbon compounds (5th ed.). London: Longmans Green and Co. p. 154.
External linksedit
Diiodomethane data sheet
New particle formation from photooxidation of diiodomethane 2012-02-11 at the Wayback Machine
January 01, 1970
diiodomethane, methylene, iodide, commonly, abbreviated, organoiodine, compound, very, dense, colorless, liquid, however, decomposes, upon, exposure, light, liberating, iodine, which, colours, samples, brownish, slightly, soluble, water, soluble, organic, solv. Diiodomethane or methylene iodide commonly abbreviated MI is an organoiodine compound Diiodomethane is a very dense colorless liquid however it decomposes upon exposure to light liberating iodine which colours samples brownish It is slightly soluble in water but soluble in organic solvents It has a very high refractive index of 1 741 and a surface tension of 0 0508 N m 1 3 Diiodomethane Ball and stick model of diiodomethane Spacefill model of diiodomethane Names Preferred IUPAC name Diiodomethane 1 Identifiers CAS Number 75 11 6 Y 3D model JSmol Interactive image Beilstein Reference 1696892 ChemSpider 6106 Y ECHA InfoCard 100 000 765 EC Number 200 841 5 MeSH methylene iodide PubChem CID 6346 RTECS number PA8575000 UNII 3J731705OX Y CompTox Dashboard EPA DTXSID4058784 InChI InChI 1S CH2I2 c2 1 3 h1H2 YKey NZZFYRREKKOMAT UHFFFAOYSA N Y SMILES ICI Properties Chemical formula C H 2I 2 Molar mass 267 836 g mol 1 Appearance Colorless liquid Density 3 325 g mL 1 3325 kg m3 Melting point 5 4 to 6 2 C 41 6 to 43 1 F 278 5 to 279 3 K Boiling point 182 1 C 359 7 F 455 2 K Solubility in water 1 24 g L 1 at 20 C 2 Henry s lawconstant kH 23 mmol Pa 1 kg 1 Magnetic susceptibility x 93 10 10 6 cm3 mol Structure Coordination geometry Tetragonal Molecular shape Tetrahedron Thermochemistry Heat capacity C 133 81 J K 1 mol 1 Std enthalpy offormation DfH 298 67 7 69 3 kJ mol 1 Std enthalpy ofcombustion DcH 298 748 4 747 2 kJ mol 1 Hazards GHS labelling Pictograms Signal word Danger Hazard statements H302 H315 H318 H335 Precautionary statements P261 P280 P305 P351 P338 NFPA 704 fire diamond 310 Flash point 110 C 230 F 383 K Safety data sheet SDS hazard com Related compounds Related alkanes haloalkanes MethaneMethyl iodideIodoformCarbon tetraiodideDifluoromethaneDichloromethaneDibromomethane Except where otherwise noted data are given for materials in their standard state at 25 C 77 F 100 kPa Y verify what is Y N Infobox references Contents 1 Uses 2 Preparation 3 Safety 4 References 5 External linksUses editBecause of its high density diiodomethane is used in the determination of the density of mineral and other solid samples It can also be used as an optical contact liquid in conjunction with the gemmological refractometer for determining the refractive index of certain gemstones Diiodomethane is a reagent for installing the CH2 group In the Simmons Smith reaction it is a source of methylene 4 In fact the Simmons Smith reaction does not produce free carbene but proceeds via Zn CH2I intermediates Diiodomethane is also a source of the equivalent of CH2 2 The synthesis of Fe2 CH2 CO 8 illustrates this reactivity 5 Na2Fe2 CO 8 CH2I2 Fe2 CH2 CO 8 2 NaIPreparation editDiiodomethane can be prepared from the widely available solvent dichloromethane by the action of sodium iodide in acetone in the Finkelstein reaction 6 CH2Cl2 2 NaI CH2I2 2 NaCl It can also be prepared by reducing iodoform with elemental phosphorus 7 or sodium arsenite 6 CHI3 Na3AsO3 NaOH CH2I2 NaI Na3AsO4Safety editAlkyl iodides are alkylating agents which are potential mutagens References edit methylene iodide Compound Summary PubChem Compound USA National Center for Biotechnology Information 26 March 2005 Identification ad Related Records Retrieved 27 February 2012 Diiodomethane Website of Kruss Archived 2013 12 01 at the Wayback Machine 8 10 2009 Two cyclopropanation reactions Smith R D Simmons H E Norcarane Organic Syntheses Collected Volumes vol 5 p 855 Ito Y Fujii S Nakatuska M Kawamoto F Saegusa T 1988 One Carbon Ring Expansion Of Cycloalkanones To Conjugated Cycloalkenones 2 Cyclohepten 1 one Organic Syntheses Collected Volumes vol 6 p 327 Sumner Charles E Riley Paul E Davis Raymond E Pettit R 1980 Synthesis Crystal Structure and Chemical Reactivity of Octacarbonyl m methylene diiron Journal of the American Chemical Society 102 5 1752 1754 doi 10 1021 ja00525a062 a b Roger Adams C S Marvel 1921 Methylene Iodide Organic Syntheses 1 57 doi 10 15227 orgsyn 001 0057 Miller William Allen 1880 Elements of Chemistry Chemistry of carbon compounds 5th ed London Longmans Green and Co p 154 External links editDiiodomethane data sheet New particle formation from photooxidation of diiodomethane Archived 2012 02 11 at the Wayback Machine Retrieved from https en wikipedia org w index php title Diiodomethane amp oldid 1218896097, wikipedia, wiki, book, books, library,
