Kohlenstofftetrabromid Chemische Eigenschaften,Einsatz,Produktion Methoden
ERSCHEINUNGSBILD
FARBLOSE KRISTALLE.
CHEMISCHE GEFAHREN
Zersetzung beim Erhitzen unter Bildung giftiger und ?tzender Rauche. Reagiert mit Alkalimetallen unter Explosionsgefahr.
ARBEITSPLATZGRENZWERTE
TLV: 0,1 ppm (als TWA); 0,3 ppm (als STEL) (ACGIH 2005).
MAK nicht festgelegt (DFG 2005).
AUFNAHMEWEGE
Aufnahme in den K?rper durch Inhalation und durch Verschlucken.
INHALATIONSGEFAHREN
Beim Verdampfen bei 20°C tritt langsam eine gesundheitssch?dliche Kontamination der Luft ein.
WIRKUNGEN BEI KURZZEITEXPOSITION
WIRKUNGEN BEI KURZZEITEXPOSITION: Tr?nenreizend. Die Substanz ver?tzt die Augen und reizt die Haut und die Atemwege. M?glich sind Auswirkungen auf Lunge, Leber und Nieren. Exposition gegenüber hohen Konzentrationen kann zu Bewusstlosigkeit führen.
WIRKUNGEN NACH WIEDERHOLTER ODER LANGZEITEXPOSITION
M?glich sind Auswirkungen auf die Leber.
LECKAGE
Verschüttetes Material in Beh?ltern sammeln; falls erforderlich durch Anfeuchten Staubentwicklung verhindern. Reste sorgf?ltig sammeln. An sicheren Ort bringen. Pers?nliche Schutzausrüstung: Atemschutzger?t, P2-Filter für sch?dliche Partikel.
R-S?tze Betriebsanweisung:
R37/38:Reizt die Atmungsorgane und die Haut.
R41:Gefahr ernster Augensch?den.
R36:Reizt die Augen.
R26:Sehr giftig beim Einatmen.
R52/53:Sch?dlich für Wasserorganismen, kann in Gew?ssern l?ngerfristig sch?dliche Wirkungen haben.
S-S?tze Betriebsanweisung:
S26:Bei Berührung mit den Augen sofort gründlich mit Wasser abspülen und Arzt konsultieren.
S36:DE: Bei der Arbeit geeignete Schutzkleidung tragen.
S45:Bei Unfall oder Unwohlsein sofort Arzt zuziehen (wenn m?glich, dieses Etikett vorzeigen).
S27:Beschmutzte, getr?nkte Kleidung sofort ausziehen.
S24:Berührung mit der Haut vermeiden.
S61:Freisetzung in die Umwelt vermeiden. Besondere Anweisungen einholen/Sicherheitsdatenblatt zu Rate ziehen.
Beschreibung
Carbon tetrabromide is considered a highly toxic chemical,
may be fatal if inhaled, swallowed, or absorbed through skin.
It is metabolized in vitro to produce carbon monoxide but
the in vivo significance has not been established. Under
anaerobic reducing conditions it forms complexes with
ferrous cytochrome P450. Carbon monoxide is detected as
a metabolic product of the interaction. Carbon tetrabromide’s
production and use in organic syntheses may
result in its release to the environment through various waste
streams. Carbon tetrabromide has been isolated from red
algae, Asparagopsis toxiformis, found in the ocean near Hawaii.
It was detected in water from treated chlorinated seawater
used for drinking at oil platforms. Occupational exposure to
carbon tetrabromide may occur through inhalation and
dermal contact with this compound at workplaces where it is
produced or used. The general population may be exposed to
carbon tetrabromide via ingestion of drinking water. Acute
exposures to high concentrations may cause upper respiratory
tract irritation and injury to lungs, liver (hepatotoxicity)
and kidneys (nephrotoxicity). Chronic exposure effects at
very low levels will be almost entirely limited to liver injury.
It is a potent lachrymator even at low exposure concentrations.
Although carbon tetrabromide may release bromine
ions during metabolism, clinical bromism is not expected to
occur.
Chemische Eigenschaften
Carbon tetrabromide, is a colorless powder,
white crystalline solid, or yellow-brown crystals. Slight
odor
Verwenden
Carbon tetrabromide is used to a limited extent as a chemical
intermediate. It has been isolated from red algae, Asparagopsis
toxiformis, found in the ocean near Hawaii.
Definition
ChEBI: A one-carbon compound substituted by 4 bromo groups.
Application
Carbon tetrabromide (CBr4) is a multifunctional chemical reagent widely used in chemical and pharmaceutical industries. It mainly includes:
(1) As a thiophilic reagent, it promotes the one-pot oxidative condensation of amines with N,N'-disubstituted thioureas to give a variety of guanidine derivatives
[1].
(2) As a bromine radical precursor, used in the electrochemical radical bromination and cyclisation sequence of enoic acid to prepare bromomethylated γ-lactone derivatives
[2].
(3) As a precursor of hydrogen atom transfer reagent, used to generate aromatic carbonyl compounds
[3].
(4) As raw materials or intermediates for organic synthesis. Synthesis of N-sulfonylformamidine from CBr4 and formamide under UVA irradiation. Activated imine intermediates (Vilsmeier-Haack reagent derivatives) were obtained via a photoinduced reaction between CBr4 and formamide
[4].
Allgemeine Beschreibung
A colorless crystalline solid. Much more dense than water and insoluble in water. Toxic by ingestion. Vapors are narcotic in high concentration. Used to make other chemicals.
Air & Water Reaktionen
Insoluble in water.
Reaktivit?t anzeigen
Carbon tetrabromide is incompatible with the following: Strong oxidizers, hexacyclohexyldilead, lithium .
Hazard
A poison; narcotic in high concentration.
Liver damage, eye, skin, and upper respiratory tract
irritant.
Health Hazard
Highly toxic, may be fatal if inhaled, swallowed or absorbed through skin. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution.
Brandgefahr
Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Containers may explode when heated. Runoff may pollute waterways.
Sicherheitsprofil
Poison by
subcutaneous and intravenous routes.
Narcotic in high concentration. Mixture
with Li particles is an impact-sensitive
explosive. Explodes on contact with
hexacyclohexylddead. When heated to
decomposition it emits toxic fumes of Br-.
See also CHLORINATED
HYDROCARBONS, ALIPHATIC.
Environmental Fate
Carbon tetrabromide inhibits protein synthesis and causes
lipid peroxidation, both of which may be involved in cell injury
or death mediated by free radicals.
Versand/Shipping
UN2516 Carbon tetrabromide, Hazard Class:
6.1; Labels: 6.1-Poisonous materials.
l?uterung methode
Reactive bromide is removed from CBr4 by refluxing with dilute aqueous Na2CO3, then steam distilling, crystallising from EtOH, and drying in the dark under vacuum. [Sharpe & Walker J Chem Soc 157 1962.] It can be sublimed at 70o and low pressure. [Beilstein 1 IV 85.]
Inkompatibilit?ten
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, lithium and hexacyclohexyldiilead, since violent reactions may occur.
Waste disposal
Purify by distillation and
return to suppliers.
Kohlenstofftetrabromid Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
