Rhodanwasserstoffsäure

Thiocyanic Acid

HCID 781CAS 463-56-9

Grundinformationen

Standard-SMILES
N#CS
InChIKey
ZMZDMBWJUHKJPS-UHFFFAOYSA-N
Summenformel
HSCN
Durchschnittliche Molmasse
59,09 g/mol
Monoisotopische Masse
58,98297003

Überblick

Thiocyanic acid is a hydracid that is cyanic acid in which the oxygen is replaced by a sulfur atom. It has a role as an Escherichia coli metabolite. It is an organosulfur compound, a hydracid and a one-carbon compound. It is a conjugate acid of a thiocyanate. It is a tautomer of an isothiocyanic acid.

Namen und Bezeichner

Bevorzugter Name
Thiocyanic Acid
IUPAC
thiocyanic acid
Lokaler Name
Rhodanwasserstoffsäure
Englischer Name
Thiocyanic acid
Summenformel
CHNS
Molmasse
59.09

Namen und Synonyme

thiocyanic acid463-56-9Sulfocyanic acidhydrogen thiocyanatenitridosulfanidocarbonhydrogen rhodanideA5KWW7N91VCHEBI:29200DTXSID7047221nitridosulfanidocarbon;thiocyanic acidRefChem:189475DTXCID5027221
Weitere Namen anzeigen
207-337-4ThiocyansaeureHSCNsulfonium cyanideN#C-SH[CN(SH)]HS-C#N[C(N)(SH)]

Datenbank-Bezeichner

CAS
463-56-9
PubChem CID
781
DTXSID
DTXSID7047221
ChEMBL
CHEMBL84336
ChEBI
CHEBI:29200
UNII
A5KWW7N91V
EC Number
207-337-4
Nikkaji
J402B

Eigenschaften

Berechnete Struktureigenschaften

XLogP
0,6
Polarare Oberfläche (TPSA)
24,8 Ų
H-Brücken-Donoren
1
H-Brücken-Akzeptoren
2
Frei drehbare Bindungen
0
Schwere Atome
3

Experimentelle und physikochemische Eigenschaften

Chemical Classes · 2 Einträge

Other Classes -> Organic Acids

Ionic Liquids

SpringerMaterials PropertiesMoessbauer quadrupole effect
LogP0.58 (estimated)
SolubilitySolubility in water: good
Melting Point5 °C
Vapor DensityRelative vapor density (air = 1): 2.0

Physikochemische Eigenschaften

Schmelzpunkt
-110 °C · -110 °C
Siedepunkt
-87.78 °C · -87.78°C (estimate)
Dichte
1.228 · 1.228 (estimate)
Brechungsindex
1.464 · 1.4640 (estimate)
pka
0.93 · 0.93±0.10(Predicted)
PH
1 · pKa1= –0.87(25℃)

Sicherheit und Regulatorisches

GHS-Klassifizierung

GHS Classification · 6 Einträge

Warning

H302: Harmful if swallowed [Warning Acute toxicity, oral]

P261, P264, P270, P271, P273, P280, P301+P317, P302+P352, P304+P340, P317, P321, P330, P362+P364, and P501 (click each P-code to see the statement)

Warning

H302: Harmful if swallowed [Warning Acute toxicity, oral]

P261, P264, P270, P271, P273, P280, P301+P317, P302+P352, P304+P340, P317, P321, P330, P362+P364, and P501 (click each P-code to see the statement)

Gefahrenhinweise

Fire HazardsNot combustible. Gives off irritating or toxic fumes (or gases) in a fire.
Hazards SummaryA very strong acid; [Merck Index] Polymerizes on warming; Chronic exposure may cause hypothyroidism; [ICSC] See Sodium thiocyanate.
EC ClassificationSymbol: Xn; R: 20/21/22-32-52/53; S: (2)-13-61
Chemical DangersThe substance polymerizes due to warming. Decomposes on heating. This produces toxic fumes. Reacts violently with strong bases and strong oxidants. This produces toxic fumes including hydrogen cyanide.
Physical DangersThe vapour is heavier than air.
Packaging and LabellingDo not transport with food and feedstuffs.

Sicherheit und Schutzausrüstung

Fire FightingIn case of fire in the surroundings, use appropriate extinguishing media.
First Aid Measures · 4 Einträge

Fresh air, rest.

Remove contaminated clothes. Rinse and then wash skin with water and soap.

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

Rinse mouth. Give one or two glasses of water to drink. Refer for medical attention .

Safe StorageSeparated from strong oxidants, strong bases and food and feedstuffs. Ventilation along the floor.
Spillage Disposal · 1 Eintrag

Personal protection: filter respirator for acid gases and vapours adapted to the airborne concentration of the substance. Collect leaking and spilled liquid in covered containers as far as possible. Carefully collect remainder. Then store and dispose of according to local regulations.

Eye PreventionWear safety spectacles.
Fire PreventionNO contact with acids, bases or oxidizing agents.

Toxikologische Informationen

Treatment · 2 Einträge

In cases of thiocyanate exposure, get fresh air and medical attention. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. If swallowed, do not induce vomiting but give large quantities of water. Immediately flush skin with plenty of water for at least 15 minutes in case of exposure to skin or the eyes. (L217)

Antidotes to cyanide poisoning include hydroxocobalamin and sodium nitrite, which release the cyanide from the cytochrome system, and rhodanase, which is an enzyme occurring naturally in mammals that combines serum cyanide with thiosulfate, producing comparatively harmless thiocyanate. Oxygen therapy can also be administered. (L97)

Health Effects · 2 Einträge

Thiocyanates are known to affect the thyroid glands, reducing the ability of the gland to produce hormones that are necessary for the normal function of the body. Exposure to high levels of cyanide for a short time harms the brain and heart and can even cause coma and death. (L191)

Exposure to high levels of cyanide for a short time harms the brain and heart and can even cause coma, seizures, apnea, cardiac arrest and death. Chronic inhalation of cyanide causes breathing difficulties, chest pain, vomiting, blood changes, headaches, and enlargement of the thyroid gland. Skin contact with cyanide salts can irritate and produce sores. (L96, L97)

Adverse EffectsNeurotoxin - Other CNS neurotoxin
Exposure Routes · 3 Einträge

The substance can be absorbed into the body by inhalation of its vapour and by ingestion.

Oral (L191); inhalation (L191) ; dermal (L191)

Inhalation (L96) ; oral (L96) ; dermal (L96)

Toxicity Summary · 2 Einträge

Thiocyanate (sulphocyanate or SCN) is believed to be a goitrogenic compound. It is a competitive inhibitor of the human thyroid sodium/iodide symporter NIS. Thus, the adverse effects of thiocyanate overload are especially noticeable when iodine availability is low. Intake of goitrogenic substances causes an adaptive increase in T3‰ЫЄs binding to brain nuclear receptors and in the activity of type II 5'-deiodinase, which generates T3 from T4. This altered function and availability of T3 is detrimental to the developing brain. Thiocyanate is also known to modulate activity of mammalian peroxidases. For instance, eosinophil peroxidase has been implicated in promoting oxidative tissue damage in a variety of inflammatory conditions, including asthma. Thiocyanate also acts as inhibitor to carbonic anhydrase, which catalyzes the rapid conversion of carbon dioxide to bicarbonate and protons. (A139, A143, A149) Organic nitriles decompose into cyanide ions both in vivo and in vitro. Consequently the primary mechanism of toxicity for organic nitriles is their production of toxic cyanide ions or hydrogen cyanide. Cyanide is an inhibitor of cytochrome c oxidase in the fourth complex of the electron transport chain (found in the membrane of the mitochondria of eukaryotic cells). It complexes with the ferric iron atom in this enzyme. The binding of cyanide to this cytochrome prevents transport of electrons from cytochrome c oxidase to oxygen. As a result, the electron transport chain is disrupted and the cell can no longer aerobically produce ATP for energy. Tissues that mainly depend on aerobic respiration, such as the central nervous system and the heart, are particularly affected. Cyanide is also known produce some of its toxic effects by binding to catalase, glutathione peroxidase, methemoglobin, hydroxocobalamin, phosphatase, tyrosinase, ascorbic acid oxidase, xanthine oxidase, succinic dehydrogenase, and Cu/Zn superoxide dismutase. Cyanide binds to the ferric ion of methemoglobin to form inactive cyanmethemoglobin. (L97)

Organic nitriles decompose into cyanide ions both in vivo and in vitro. Consequently the primary mechanism of toxicity for organic nitriles is their production of toxic cyanide ions or hydrogen cyanide. Cyanide is an inhibitor of cytochrome c oxidase in the fourth complex of the electron transport chain (found in the membrane of the mitochondria of eukaryotic cells). It complexes with the ferric iron atom in this enzyme. The binding of cyanide to this cytochrome prevents transport of electrons from cytochrome c oxidase to oxygen. As a result, the electron transport chain is disrupted and the cell can no longer aerobically produce ATP for energy. Tissues that mainly depend on aerobic respiration, such as the central nervous system and the heart, are particularly affected. Cyanide is also known produce some of its toxic effects by binding to catalase, glutathione peroxidase, methemoglobin, hydroxocobalamin, phosphatase, tyrosinase, ascorbic acid oxidase, xanthine oxidase, succinic dehydrogenase, and Cu/Zn superoxide dismutase. Cyanide binds to the ferric ion of methemoglobin to form inactive cyanmethemoglobin. (L97)

Signs and Symptoms · 2 Einträge

Symptoms of thiocyanate exposure include rapid, deep breathing and shortness of breath, followed by convulsions (seizures) and loss of consciousness. (L191)

Cyanide poisoning is identified by rapid, deep breathing and shortness of breath, general weakness, giddiness, headaches, vertigo, confusion, convulsions/seizures and eventually loss of consciousness. (L96, L97)

Sicherheitsdaten

tsca
TSCA listed
risk_code
20/21/22-32-52/53
hazard_code
Xn
safety_code
13-61

Chemie und Industrie

Pharmakologische Informationen

Metabolism/Metabolites · 2 Einträge

Thiocyanates can appear in the body after metabolization of cyanides by rhodanese. When thiocyanates enter the body, they normally breaks down in aqueous solution to yield sulfate ions. However, thiocyanates are also found in the thyroid fluids. Immediately following exposure to thiocyanate containing solutions, the cystic fibrosis conductance regulator Cl‰ЫТ channel exhibits high unitary SCN‰ЫТ conductance and anomalous mole fraction behaviour. Thiocyanates is normally excreted in urine. (A140, A142, A143, A144) Organic nitriles are converted into cyanide ions through the action of cytochrome P450 enzymes in the liver. Cyanide is rapidly absorbed and distributed throughout the body. Cyanide is mainly metabolized into thiocyanate by either rhodanese or 3-mercaptopyruvate sulfur transferase. Cyanide metabolites are excreted in the urine. (L96)

Organic nitriles are converted into cyanide ions through the action of cytochrome P450 enzymes in the liver. Cyanide is rapidly absorbed and distributed throughout the body. Cyanide is mainly metabolized into thiocyanate by either rhodanese or 3-mercaptopyruvate sulfur transferase. Cyanide metabolites are excreted in the urine. (L96)

Verwendung und Herstellung

Uses · 1 Eintrag

Exposure occurs from breathing air and drinking water, touching soil or water containing thiocyanate, or eating foods that contain thiocyanate. Thiocyanates are present in water primarily because of discharges from coal processing, extraction of gold and silver, and mining industries. Thiocyanate is the major product formed from cyanide that passes into the body as the body attempts to rid itself of cyanide, thus exposure to cyanide also results in exposure to thiocyanate. (L191)

General Manufacturing InformationThiocyanic acid: INACTIVE
Anwendungen · 1 Eintrag

VerwendenThiocyanic acid can be used to prepare thiocyanates, esters, various thiocyanates, and cyanides. SCN ions are excellent ligands. A particularly sensitive reaction of SCN ions is the formation of various red complexes with Fe. Therefore, potassium thiocyanate or ammonium thiocyanate are commonly used as reagents for testing for Fe.

Ergänzende Hinweise

Definitionthiocyanic acid: An unstable gas, HSCN.

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