MERCURIC ACETATE химические свойства, назначение, производство
Описание
Mercury (II) acetate is the chemical compound with the formula Hg(O2CCH3)2. Commonly abbreviated Hg (OAc)2, this compound is employed as a reagent to generate organomercury compounds from unsaturated organic precursors.
Химические свойства
Mercuric acetate, Hg(C2H3O2)2 , is a toxic, light-sensitive white powder, soluble in water,alcohol,and acetic acid. On exposure to heat, mercuric acetate produces toxic fumes of mercury/mercuric oxide. Mercuric acetate is incompatible with chromic acid, chromic anhydride, nitric acid, perchloric acid, permanganates, sodium peroxide, potassium hydroxide, hydrogen peroxides, acid anhydrides, and strong oxidising agents.
Физические свойства
Mercury(II) acetate is a crystalline solid consisting of isolated Hg(OAc)2 molecules with Hg-O distances of 2.07 ?. Three long, weak intermolecular Hg···O bonds of about 2.75 ? are also present,resulting in a slightly distorted square pyramidal coordination geometry at Hg.
Использование
Mercuric acetate is used as an oxidizing agent in organic synthesis. It is used in oxymercuration of double bonds. Mercuric acetate is used in non-aqueous titration. It is employed in the manufacture of phenyl mercury compounds which have pharmaceutical applications. It removes the acetamidomethyl protecting group from protected thiol, and converts thiocarbonate esters into dithiocarbonates. It promotes the addition of hydroxide and alkoxide across carbon-carbon double bonds.
Реакции
Arenes undergo "mercuration" upon treatment with Hg(OAc)2. The one acetate group that remains on mercury can be displaced by chloride :
C6H5OH + Hg(OAc)2 → C6H4(OH)-2-HgOAc + HOAc
C6H4(OH)-2-HgOAc + NaCl → C6H4(OH)-2-HgCl + NaOAc
The Hg2+ center binds to alkenes, inducing the addition of hydroxide and alkoxide. For example, treatment of methylacrylate with mercuric acetate in methanol gives an α - mercuri ester :
Hg(OAc)2 + CH2 = CHCO2CH3 + CH3OH → CH3OCH2CH(HgOAc)CO2CH3+ HOAc
Mercury(II) has a high affinity for sulfur ligands. Hg (OAc)2 can be used as a reagent to remove the acetamidomethyl protecting group, which is used to "protect" thiol groups in organic synthesis. Similarly Hg(OAc)2 is a standard reagent to convert thiocarbonate esters into dithiocarbonates:
(RS)2C=S + H2O + Hg(OAc)2 → (RS)2C=O + HgS + 2 HOAc
Mercury (II) acetate is used for oxymercuration reactions.
Общее описание
White crystalline solid with an odor of vinegar. Sensitive to light. Density 3.25 g / cm3. Toxic by inhalation (dust, etc.) and by ingestion.
Реакции воздуха и воды
Water soluble. Decomposed by water to form a yellow insoluble product.
Профиль реактивности
MERCURIC ACETATE is incompatible with acetylene, ammonia, chlorine dioxide, azides, calcium (amalgam formation), sodium carbide, lithium, rubidium, and copper .
Опасность
Toxic by ingestion, inhalation, and skin
absorption; strong irritant.
Угроза здоровью
MERCURIC ACETATE may cause death by hypovolemic shock or kidney failure. Chronic exposure may lead to kidney failure.
Пожароопасность
When heated to decomposition, MERCURIC ACETATE emits toxic fumes of mercury. Avoid light.
Профиль безопасности
Poison by ingestion,
intravenous, intraperitoneal, and
subcutaneous routes. Moderately toxic by
skin contact. An experimental teratogen.
Experimental reproductive effects. Mutation
data reported. When heated to
decomposition it emits toxic fumes of Hg.
See also MERCURY COMPOUNDS.
Возможный контакт
Mercuric acetate is used chiefly for
mercuration of organic compounds; for the absorption ofethylene; as a chemical intermediate for phenylmercuric
acetate; a mildewcide; and other organomercury compounds. It is used as a catalyst in organic synthesis; and in
the manufacture of pharmaceuticals.
Перевозки
UN1629 Mercury acetate, Hazard Class: 6.1;
Labels: 6.1-Poisonous materials.
Методы очистки
Recrystallise it from glacial acetic acid. POISONOUS. [Beilstein 2 IV 114.]
Несовместимости
Incompatible with oxidizers (chlorates,
nitrates, peroxides, permanganates, perchlorates, chlorine,
bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases,
strong acids, oxoacids, epoxides. Light and heat can cause
decomposition.
MERCURIC ACETATE препаратная продукция и сырье
сырьё
препарат