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|Section2= |Section3= |Section4= |Section5= |Section6= }} Methyl iodide, also called iodomethane, and commonly abbreviated "MeI", is the chemical compound with the formula CH3I. It is a dense, colorless, volatile liquid. In terms of chemical structure, it is related to methane by replacement of one hydrogen atom by an atom of iodine. It is naturally emitted by rice plantations in small amounts. It is also produced in vast quantities estimated to be greater than 214,000 tons annually by algae and kelp in the world's temperate oceans, and in lesser amounts on land by terrestrial fungi and bacteria. It is used in organic synthesis as a source of methyl groups. Methyl iodide had been approved for use as a pesticide by the United States Environmental Protection Agency in 2007 as a pre-plant biocide used to control insects, plant parasitic nematodes, soil borne pathogens, and weed seeds.〔Zitto, Kelly 〕 The compound was registered for use as a preplant soil treatment for field grown strawberries, peppers, tomatoes, grape vines, ornamentals and turf and nursery grown strawberries, stone fruits, tree nuts, and conifer trees. After the discovery phase in a consumer lawsuit, the manufacturer withdrew the fumigant citing its lack of market viability.〔("Maker of methyl iodide scraps controversial pesticide" ) ''San Jose Mercury News'' March 20, 2012〕 ==Preparation and handling== Methyl iodide is formed via the exothermic reaction that occurs when iodine is added to a mixture of methanol with red phosphorus. The iodinating reagent is phosphorus triiodide that is formed ''in situ:'' :3 CH3OH + PI3 → 3 CH3I + H3PO3 Alternatively, it is prepared from the reaction of dimethyl sulfate with potassium iodide in the presence of calcium carbonate:〔 :(CH3O)2SO2 + KI → CH3I + CH3OSO2OK Methyl iodide can also be prepared by the reaction of methanol with aqueous hydrogen iodide: : CH3OH + HI → CH3I + H2O The generated methyl iodide can be distilled from the reaction mixture. Methyl iodide may also be prepared by treating iodoform with potassium hydroxide and dimethyl sulfate under 95% ethanol.〔J. Chem. Educ., 1933, 10 (12), p 747 ''(Preparation of methyl or ethyl iodide from iodoform. )''〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Methyl iodide」の詳細全文を読む スポンサード リンク
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