Name | Thiolacetic acid |
Synonyms | usafek-p-737 Usaf EK-P-737 Thioessigsure THIOESSIGSAEURE Thioacetic acid EthanthiolicAcid Thiolacetic acid thionoaceticacid Ethanethioic acid ethylsulfuric acid ethanethioic S-acid |
CAS | 507-09-5 |
EINECS | 208-063-8 |
InChI | InChI=1/C2H4OS/c1-2(3)4/h1H3,(H,3,4) |
Molecular Formula | C2H4OS |
Molar Mass | 76.12 |
Density | 1.065 g/mL at 25 °C(lit.) |
Melting Point | -17 °C |
Boling Point | 97 °C |
Flash Point | 52°F |
JECFA Number | 1676 |
Water Solubility | 27 g/L (15 ºC) (hydrolyse) |
Solubility | 27g/l (slow decomposition) |
Vapor Presure | 1 hPa (20 °C) |
Appearance | Liquid |
Color | Clear colorless to pale yellow |
Merck | 14,9320 |
BRN | 773684 |
pKa | 3.33(at 25℃) |
PH | 1.8 (100g/l, H2O, 20℃)Hydrolysis |
Storage Condition | Store below +30°C. |
Stability | Stable. Flammable. Incompatible with metals, strong oxidizing agents. |
Refractive Index | n20/D 1.465(lit.) |
Physical and Chemical Properties | Density 1.065 melting point -17°C boiling point 88-93°C refractive index 1.463-1.465 flash point 18°C water-soluble 27g/L (15°C) (hydrolyse) |
Use | Used as pharmaceutical, Flavor and Fragrance Intermediates |
Risk Codes | R11 - Highly Flammable R34 - Causes burns R22 - Harmful if swallowed R43 - May cause sensitization by skin contact R41 - Risk of serious damage to eyes |
Safety Description | S9 - Keep container in a well-ventilated place. S16 - Keep away from sources of ignition. S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S36/37/39 - Wear suitable protective clothing, gloves and eye/face protection. S45 - In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.) S28 - After contact with skin, wash immediately with plenty of soap-suds. S23 - Do not breathe vapour. |
UN IDs | UN 2436 3/PG 2 |
WGK Germany | 3 |
RTECS | AJ5600000 |
FLUKA BRAND F CODES | 13-19 |
TSCA | Yes |
HS Code | 29309070 |
Hazard Class | 3 |
Packing Group | II |
Toxicity | LD50 orally in Rabbit: 200 - 350 mg/kg |
Raw Materials | Acetic anhydride Sodium sulfide Sulfuric acid |
Downstream Products | Isobutyryl chloride captopril |
FEMA | 4210 | THIOACETIC ACID |
LogP | 0.14 |
NIST chemical information | Information provided by: webbook.nist.gov (external link) |
EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
introduction | thioacetic acid is an acid containing sulfhydryl groups, also known as thioacetic acid, ethylthionic acid, and ethylsulfuric acid. Yellow fuming liquid, with unpleasant spicy smell, active chemical properties, strong reactivity, can react with unsaturated aliphatic hydrocarbons and alcohols to prepare mercaptans. CH3COSH CH2 = CHCH3 → CH3CH2CH2SHCH3COSH CH3CH2OH → CH3CH2SH reaction with ethylene oxide, acetylthio ethanol can be prepared. CH3COSH (CH2)2O→CH3COSCH2CH2OH |
use | thioacetic acid replaces hydrogen sulfide in the laboratory, verifies cobalt and lead, determines molybdenum, synthesizes thioaldehyde and thione, and determines esterase in histochemistry, Used as tear gas, etc. This product is an acetyl sulfide and sulfhydryl agent in organic synthesis. It is mainly used for the synthesis of lipoic acid, cystine and sulfhydryl carboxylic acid, as well as hormone modifiers and antidote, cephalosporin modifiers and fungicides, polymer modifiers and additives synthesis. Used in reagents, flavors and fragrances, cosmetics, synthetic captopril, etc. Used as medicine, essence and fragrance intermediate Used as chemical reagent, precipitant and catalyst |
Preparation | Four methods for preparing thioacetic acid in the laboratory: 1. Acetic acid and phosphorus pentasulfide are reacted at 91°C, and further refined by vacuum distillation. Can be made. 5CH3COOH P2S5 → CH3COSHC2H4OS P2O52, acetyl chloride reacts with hydrogen sulfide, neutralized with dilute lye, and refined by rectification. Can be made. 3. The reaction of acetic anhydride and hydrogen sulfide can produce a finished product of thioacetic acid, and at the same time by-produce acetic acid. 4. The reaction of ketene and hydrogen sulfide can be directly prepared. |
Production method | It is obtained by co-thermal distillation of aldehydes and pentathiophosphorus. Add fine powdered phosphorus pentasulfide to glacial acetic acid. When heated to 91 ℃, start to evaporate thioacetic acid. When heated, it must be prevented from boiling. The distillation temperature must not exceed 100 ℃. The distillate is redistilled once to obtain the finished product. |
category | corroded articles |
toxicity classification | highly toxic |
acute toxicity | abdominal cavity-mouse LD50: 75 mg/kg |
flammability hazard characteristics | combustible; easily decomposed into acetic acid and toxic hydrogen sulfide gas |
storage and transportation characteristics | warehouse ventilation and low temperature drying; Store separately from oxidant and alkali. |
fire extinguishing agent | sand, foam, mist water, carbon dioxide |