Chlorotriethylsilane (C6H15ClSi) is an organosilicon material of enormous industrial use. It is used mainly in the production of silicone oils, resins and other polysiloxanes, as well as as a capping compound in the production of ethyl silicone oils and rubber. Chlorotriethylsilane also acts as a coupling agent, which helps the organic and inorganic substances get along better by changing the surface properties, such as hydrophobicity and adhesion. It appears as a clear to pale yellow liquid, which smells strongly. Principal properties are molecular weight of 150.72 g/mol, density of approximately 0.898 g/mL (25 °C), boiling point of 142-144 °C, melting point of -50 °C, and flash point of 29 °C.
This is a complete protocol for the synthesis of triethylsilane from chlorotriethylsilane with a focus on safety and high purity. The procedures have to be closely observed in order to achieve a safe, efficient synthesis and to shield operators from chemical exposure.
Experimental Reagents
Sodium hydride (NaH), Trimethyl borate (B(OCH3)3), Sodium trihydroxyborohydride solution, chlorotriethylsilane, Appropriate organic solvent.
| Catalog | Product Name | Order |
| ACM723466 | Chlorotriethylsilane | Inquiry |
Synthesis Steps of Triethylsilane
Triethylsilane can be produced by inert reaction of sodium trihydroxyborohydride and trimethyl borate followed by chlorotriethylsilane. Each step is essential for maximum production and purity.
Step 1: Preparation of Sodium Trihydroxyborohydride
The precursor to this is sodium trihydroxyborohydride which is prepared as a precursor by the reaction of sodium hydride with trimethyl borate. The processing is done on nitrogen, so that the room is anhydrous and oxygenless.
Add sodium hydride and the chosen solvent to a reaction flask. Under a nitrogen atmosphere, cool the mixture to between -50 °C and 10°C Slowly add trimethyl borate, maintaining the low temperature and stirring continuously. Allow the reaction to proceed with stirring for 1-5 hours, ensuring complete conversion to sodium trihydroxyborohydride. The resulting sodium trihydroxyborohydride is a reactive intermediate that remains in solution for further synthesis steps.
Step 2: Addition of Chlorotriethylsilane
Under a nitrogen atmosphere, slowly add chlorotriethylsilane to the sodium trihydroxyborohydride solution. Control the reaction temperature to prevent any exothermic spikes. Stir the mixture for 1-5 hours at room temperature to complete the reaction. Insoluble wastes (including NaCl) forming in this step have to be scraped off to get the product you want. Filtration is typically used to separate these by-products.
Step 3: Purification by Distillation
To ensure the purity of chlorotriethylsilane, the reaction mixture undergoes fractional distillation under normal pressure. This step separates chlorotriethylsilane from residual solvent and any minor impurities.
Filter the reaction mixture to remove insoluble by-products. Subject the filtrate to fractional distillation. Collect the main fraction, which contains purified chlorotriethylsilane, at its boiling point (142-144°C).
Safety and Handling Precautions
Chlorotriethylsilane is very hazardous because of its reactivity and toxicity. You must store, handle, and dispose of it safely to avoid dangerous exposure.
Storage Conditions:
Put in a refrigerator in a dry, air-conditioned place, not above 30°C. Ventilate and light in an explosion-proof area because the substance is flammable. Keep tubes well-closed and away from oxidizers and bases.
Protective Measures:
Anyone working with chlorotriethylsilane must wear safety goggles, gloves, and respiratory protection (self-contained breathing device or air-purifying respirator). You must do everything under an inert atmosphere that doesn't let in any air or water.
Health Effects and Risks
Chlorotriethylsilane is very toxic if taken by mouth, inhalation, or skin contact. Consumption can cause severe gastrointestinal burns, and breathing the vapors can damage your lungs, make you dizzy, or drown you. Exposure for years leads to long-term respiratory problems like bronchitis or pulmonary edema. The skin or eyes could be badly burned. Although there is no carcinogenic data, articles describe potential carcinogenicity. Chlorotriethylsilane has a very high vapor density, so it can collect on low-lying surfaces, which puts explosion hazards in play. There needs to be proper ventilation and safety measures to eliminate these risks.
Reference
- Trimethoprim-Sulfamethoxazole. Mayo Clinic Proceedings (1987).
