Thioacetic acid, chemical formula CH3C (S) H, is a sulfur-containing organic acid commonly used in organic synthesis and pharmaceutical industry. This paper will introduce the chemical synthesis routes and steps of Thioacetic acid in laboratory and large chemical industry according to different applicable scenarios.
1、 Laboratory synthesis route
Thioacetic acid can be obtained by the reaction of thioacetyl chloride and nickel hydrate in the laboratory. The specific steps are as follows:
1.1 First add 5 mL of n-butyl lithium (1.6 mol/L) solution to 100 mL of anhydrous chloroform, cool to 0 ° C, then drop 6 mL of chloroform solution of thioacetic acid (0.1 mol/L), control the temperature at 0-5 ° C, and let stand for 10-15 minutes.
1.2 After the reaction, add 10 mL of deionized water, adjust the pH value to 5.5-6.5, and the solution turns orange.
1.3 Add the solution into pre-cooled nickel hydrate (0.1 mol/L) solution for reaction for 1 h, and control the temperature at 0-5 ° C.
1.4 After the reaction, filter the reaction solution to obtain a light yellow Thioacetic acid crystal. Rinse with acetic acid and dry.
2、 Large chemical synthesis route
Thioacetic acid can be synthesized by sodium carbonate sulfuration in large chemical industry. The specific steps are as follows:
2.1 Add 1.9 kg of sodium carbonate into the reactor and add proper amount of water to dissolve it.
2.2 Hydrolysis step: under normal temperature, slowly add 220L hydrogen sulfide gas (99.99%) into the reactor, the gas flow is 20L/min, and heat at the same time, control the temperature at 60-80 ° C, and react for 3-4 hours.
2.3 In order to ensure that the reaction is complete, the rate of several batches of reaction can be compared. When the rate is stable, add sufficient sodium hydroxide synchronously to make the pH value of the reaction solution reach about 7.0, and the reaction is complete.
2.4 Then the reaction solution is heated and concentrated, and the concentration is controlled to 16-20 ° Bx. Then the reaction solution is put into the bleaching tank for decolorization, and filtered again to obtain a light yellow-brown liquid containing Thioacetic acid.
2.5 Finally, add the liquid into the distillation tower and distill and purify it to obtain pure Thioacetic acid.
Summary: The above is the chemical synthesis route and steps of Thioacetic acid in laboratory and large chemical industry. Thioacetic acid can be synthesized by the reaction of thioacetic acid and nickel hydrate in the laboratory, while sodium carbonate sulfuration method is used in large chemical industry, and the pure Thioacetic acid is finally obtained after decolorization and distillation purification.
Thioacetic acid is an organic sulfur compound with strong reaction properties. Here are some of its reaction properties:
1. Reaction with alkali: Thioacetic acid can react with alkali to generate corresponding salts, such as:
CH3C(S)SH + NaOH → CH3C(S)Na + H2O
2. Oxidation reaction: Thioacetic acid can be oxidized to corresponding acid by oxidant such as hydrogen peroxide, for example:
CH3C(S)SH + H2O2 → CH3C(S)OH + H2O + S
3. Decarboxylation reaction: Thioacetic acid can generate corresponding mercaptan through decarboxylation reaction, for example:
CH3C(S)SH → CH3SH + CO
4. Alkylation reaction: Thioacetic acid can react with alkyl halides, such as:
CH3C(S)SH + CH3I → CH3C(S)SCH3
5. Reaction with metal ions: Thioacetic acid can react with some metal ions, such as:
CH3C(S)SH + Cu2+ → [Cu(CH3C(S)S)]2+
In short, Thioacetic acid has a variety of reaction properties and can react with many compounds.
Thioacetic acid is an organic compound containing sulfur. Its development history can be traced back to the end of the 19th century. The following is a brief introduction of its development history:
In 1887, the French chemist Marcelin Berthelot first synthesized a compound similar to Thioacetic acid, which he named "acide thioac é tique".
In 1895, the German chemist Arthur Hantzsch synthesized Thioacetic acid in a similar way, and found some important properties of it, such as volatile, pungent odor, and the ability to form clusters.
At the beginning of the 20th century, German chemist Carl Duisberg began to study the preparation methods and chemical properties of Thioacetic acid, and published a paper on the synthesis of Thioacetic acid in 1903.
From the beginning of the 20th century to the middle of the 20th century, the research of Thioacetic acid gradually deepened, not only improved its preparation method, but also found its application in biology, medicine and other fields, such as used as an important raw material in drug synthesis.
So far, the research of Thioacetic acid is still continuing, and people are exploring its wider application in organic synthesis, chemical biology and other fields.