クロム ヘキサカルボニル 化学特性,用途語,生産方法
解説
普通，ヘキサカルボニルクロム[Cr(CO)6]をいう．クロム ヘキサカルボニル, アセチルアセトナトクロム(Ⅱ)または(Ⅲ)錯体をピリジン中，粉末Znの存在下でカルボニル化してつくる．白色の結晶．ほかの金属カルボニルと比べて非常に安定で，空気中130 ℃ で分解する．真空中で昇華する．ベンゼン，四塩化炭素などから再結晶できる．COはCrのまわりに正八面体に配位し，Cr-C-Oは直線，Cr-C0.192 nm，C-O0.116 nm．N，P，Asなどのドナー原子，および不飽和炭化水素でCOを一部置換することができる．液体アンモニア中，金属ナトリウムを作用させると [Cr(CO)5]2－ が，NaBH4を作用させるとCr-H-Cr結合をもつ [Cr2H(CO)10]－ 錯体が得られる．[CAS 13007-92-6]
森北出版「化学辞典（第2版）
特徴
結晶学的分子対称Cs，八面体形，Cr－C 191 pm（平均）
化学的特性
white crystals or powder
物理的性質
White orthogonal crystal; density 1.77 g/cm
3; sublimes at ordinary temperatures; vapor pressure 1 torr at 48°C; decomposes at 130°C; insoluble in water and alcohols; soluble in ether, chloroform and methylene chloride.
使用
Chromiumhexacarbonyl is a volatile; air stable precursor of Chromium(0); widely used for thin film deposition - ALD and CVD. The thin films can be grown at room temperature and low pressure by laser CVD .
製造方法
Chromium hexacarbonyl is prepared by the reaction of anhydrous chromium(III) chloride with carbon monoxide in the presence of a Grignard reagent. A 60% product yield may be obtained at the carbon monoxide pressures of 35 to 70 atm. Other chromium salts may be used with carbon monoxide and Grignard reagent in the preparation. The compound may also be obtained by the reaction of a chromium salt with carbon monoxide in the presence of magnesium in ether or sodium in diglyme.
一般的な説明
White crystalline or granular solid. Sublimes at room temperature. Burns with a luminous flame.
空気と水の反応
Insoluble in water.
反応プロフィール
Chromium hexacarbonyl decomposes violently at 410° F. Chromium hexacarbonyl is decomposed by chlorine and fuming nitric acid. Chromium hexacarbonyl is incompatible with oxidizing agents.
危険性
Toxic by inhalation and ingestion.
健康ハザード
Chromium hexacarbonyl is a highly toxicsubstance by all routes of exposure. The toxiceffects are similar to those of molybdenumand tungsten carbonyls. The symptoms areheadache, dizziness, nausea, vomiting, andfever. The oral LD50 in mice is 150 mg/kgand in rats 230 mg/kg. The intravenous LD50in mice is 30 mg/kg. As a hexavalent compoundof chromium, it is a carcinogenic substance.
火災危険
Flash point data for Chromium hexacarbonyl are not available; however, Chromium hexacarbonyl is probably combustible.
職業ばく露
Chromium carbonyl is used as a catalyst for hydrogenation, isomerization, watergas shift reaction and alkylation of aromatic hydrocarbons; gasoline additive to increase octane number; preparation of chromous oxide, CrO
輸送方法
UN3466 Metal carbonyls, solid n.o.s. Hazard class 6.1. Technical name required. UN3281 Metal carbonyls, liquid n.o.s. Hazard class 6.1. Technical name required, Potential Inhalation Hazard (Special Provision 5). UN3466 Metal carbonyls, solid n.o.s. Hazard class 6.1. Technical name required.
純化方法
Wash the complex with cold EtOH, then Et2O, and allow it to dry in air. Alternatively recrystallise it from dry Et2O. This is best accomplished by placing the hexacarbonyl in a Soxhlet extractor and extracting exhaustively with dry Et2O. Pure Cr(CO)6 is filtered off and dried in air. Completely colourless refracting crystals are obtained by sublimation at 40-50o/<0.5mm in an apparatus where the collecting finger is cooled by Dry Ice and in which there is a wide short bore between the hot and cold sections to prevent clogging by the crystals. Loss of product in the crystallisation and sublimation is slight. It is important not to overdo the drying as the solid is appreciably volatile and TOXIC [vapour pressure is 0.04(8o), 1.0(48o) and 66.5(100o) mm]. Also do not allow the Et2O solutions to stand too long as a brown deposit is formed which is sensitive to light, and to avoid the possibility of violent decomposition. It sinters at 90o, decomposes at 130o, and EXPLODES at 210o. [Owen et al. Inorg Synth III 156 1950, Podall et al. J Am Chem Soc 83 2057 1961.] POISONOUS.
不和合性
Violent reaction on contact with oxidizers. Decomposed by chlorine and fuming nitric acid; sensitive to heat and light (undergoes photochemical decomposition). Many carbonyls react with water, forming toxic and flammable vapors
廃棄物の処理
Use a licensed professional waste disposal service to dispose of this material. All federal, state, and local environmental regulations must be observed. Consult with environmental regulatory agencies for guidance on acceptable disposal practices. Generators of waste containing this contaminant (>=100 kg/mo) must conform to EPA regulations governing storage, transportation, treatment, and waste disposal.
参考文献
A. Whitaker, J.W. Jeffery, Acta Crystallogr., 23, 977 (1967), DOI: 10.1107/S0365110X67004153.
クロム ヘキサカルボニル 上流と下流の製品情報
原材料
準備製品