2-Cyanoethyltriethoxysilane

English Name: 2-Cyanoethyltriethoxysilane

English Other Names: (2-Cyanoethyl)triethoxysilane; 3-(Triethoxysilyl)propionitrile; 3-triethoxysilylpropanenitrile; (2-cyanoethyl)triethoxy-silan; beta-cyanoethyltriethoxysilane

CAS Number: 919-31-3

EINECS Number: 213-050-5

Chemical Formula: C₉H₁₉NO₃Si

Molecular Weight: 217.34 g/mol

InChI InChI=1S/C9H19NO3Si/c1-4-11-14(12-5-2,13-6-3)9-7-8-10/h4-7,9H2,1-3H3
Density 0.979 g/mL (25°C)
Boiling Point 224-225°C (760 mmHg); 137°C/29 mmHg
Flash Point 86°C (186.8°F) or 70.5°C (158.9°F, closed cup)
Water Solubility: Hydrolyzes with water; solubility approximately 1300 mg/L (20°C)
Vapor Pressure 1.9 Pa (20°C); < 2 mmHg (25°C)
Refractive Index n²⁰/D 1.4140 (1.4120-1.4140)
Storage Conditions Argon purging; store in an inert gas atmosphere; avoid moisture.

Sensitivity: Sensitive to humidity.

Appearance: Colorless transparent liquid.

Specific gravity: 0.976-0.980 (25°C).

Color: Colorless.

BRN 1776392

MDL No. MFCD00019851

Hazard symbol Xi (Irritant)

Risk terms R36/37/38 (Irritation to eyes, respiratory system, and skin)

Safety terms S23-26-36-37 (Do not inhale the gas/fume/vapor/spray; in case of eye contact, immediately flush with plenty of water and seek medical attention; wear appropriate protective clothing and gloves)

Customs code 2931.90.90 (Organic-Inorganic Compounds)

Properties:
Physical properties: Colorless transparent liquid with a characteristic odor.
Density: 0.979 g/mL (25°C), slightly less than water.
Boiling point: 224-225°C (normal pressure), under reduced pressure (29… Boiling point: 137°C (mmHg)
Flash point: 70.5-86°C, flammable liquid
Refractive index: 1.4140 (20°C)
Viscosity: 1.9 mPa·s (20°C)
Melting point: -68.6°C
Chemical properties:
Hydrolysis sensitivity: Extremely sensitive to moisture; rapidly hydrolyzes in water to form silanol and ethanol, and may release hydrogen cyanide.
Thermal stability: Stable at room temperature; high-temperature decomposition may release toxic nitrogen oxides and cyanides.
Reactivity: The ethoxy group (-OCH₂CH₃) can be replaced by other nucleophilic groups; the cyano group (-CN) can participate in addition reactions.
Solubility: Soluble in most organic solvents (such as ethanol, acetone, toluene, etc.); hydrolyzes in water.
Structural characteristics: Contains a triethoxysilyl group and a cyanoethyl group in the molecule, possessing characteristics of both inorganic silanes and organic nitriles.
The Si-O-C bond is easily broken, making it a typical silane coupling agent structure.
II. Applications
1. Surface Treatment and Coating:
* Coating onto quartz and aluminum surfaces via sol-gel method to form a protective film.
* Used as a silane coupling agent in metal-polymer composites to improve interfacial adhesion.
* An alternative to traditional chromate treatment for metal surface treatment (non-toxic, low cost).

2. Nanomaterial Modification:
* Functionalized silica nanoparticles for the fabrication of solid-state electrolyte dye-sensitized solar cells (DSSCs).
* Fabrication of PVDF-based ultrafiltration membranes for antifouling applications.
* Synthesis of SBA-15 mesoporous silica for drug delivery systems.

3. Organic Synthesis:
* As a silanizing agent to introduce cyanoethyl silyl groups.
* Used in the preparation of silicon-containing polymers and organosilicon compounds.

4. Materials Science: Preparation of functional coating materials
For encapsulation and protection of electronic materials
As a crosslinking agent for the modification of silicone rubber and silicone resin
III. Preparation Methods
Main Synthetic Routes:
Method 1: Addition Method (Commonly Used in Industry)
Using triethoxysilane (HSi(OCH₂CH₃)₃) and acrylonitrile (CH₂=CH-CN) as raw materials
Hydrosilylation reaction is carried out in the presence of a platinum catalyst (such as Speier or Karstedt catalyst)
Reaction Conditions: 60-100°C, inert atmosphere
Reaction Formula: HSi(OEt)₃ + CH₂=CH-CN → (EtO)₃Si-CH₂-CH₂-CN
Method 2: Substitution Method
Trichlorosilane reacts with ethanol to generate triethoxysilane, which then reacts with cyanoethanol
Or, cyanoethyltrichlorosilane is used for alcoholysis with ethanol
Purification Method: Vacuum distillation (collected at 137°C/29) (mmHg fraction)

Trace moisture removed by molecular sieve or desiccant

Store under inert gas protection

IV. Safety Information

Hazard Overview:

GHS Hazard Category: Flammable liquid (Category 4); Skin corrosion/irritation (Category 2); Serious eye damage/eye irritation (Category 2A); Specific target organ toxicity (single exposure, Category 3, respiratory irritation)

NFPA Classification: Health hazard 2, Fire hazard 1, Reactivity 0

Health Hazards:
Acute Toxicity: Oral LD₅₀ in rats: 5630 mg/kg (Low toxicity)
Skin contact: Causes skin irritation, may lead to redness, swelling, and itching.
Eye contact: Causes severe eye irritation, may lead to corneal damage.
Inhalation: May cause respiratory irritation, coughing, and difficulty breathing; vapors may cause dizziness and headache.
Ingestion: May cause gastrointestinal upset, nausea, and vomiting.
Long-term exposure: Repeated exposure may lead to skin sensitization.
Environmental hazards: Harmful to aquatic life. Do not allow undiluted or large quantities of product to come into contact with groundwater, waterways, or sewage systems. Can hydrolyze in the environment, producing ethanol and silanols.
First aid measures:
Inhalation: Immediately move to fresh air, keep the airway open, perform artificial respiration if necessary, and seek medical attention.
Skin contact: Immediately wash with soap and plenty of water for at least 15 minutes, remove contaminated clothing, and seek medical attention.
Eye contact: Immediately flush with plenty of water for at least 15 minutes, lifting eyelids and rinsing thoroughly, and seek medical attention.
Ingestion: Rinse mouth with water, do not induce vomiting, and seek immediate medical attention.
Firefighting measures: Use dry powder, carbon dioxide, foam, or sand to extinguish the fire.
Do not use direct water flow (may spread the fire). Firefighters must wear gas masks and protective clothing. The fire may produce toxic nitrogen oxides, carbon monoxide, and cyanide fumes.

Leakage Emergency Handling:
Eliminate ignition sources and wear protective equipment.
Collect the leaked material with inert absorbent materials (such as sand or vermiculite).
Prevent the leaked material from entering sewers or water bodies.
Flush the leaked area with plenty of water (pay attention to wastewater treatment).
Handling and Storage:
Operate in a well-ventilated area using explosion-proof ventilation equipment.
Operators must be specially trained and wear protective eyewear, gloves, and gas masks. Keep away from heat, sparks, open flames, and oxidizers.
Store in a cool, dry, well-ventilated warehouse at a temperature not exceeding 30°C.
Keep containers sealed and protected with argon or nitrogen gas.
Store separately from oxidizers, acids, and alkalis.
Disposal: Dispose of according to local regulations; incineration is recommended.
Hydrolysis treatment should be performed before disposal to reduce toxicity.
Do not discharge into sewers or the environment.
Regulatory Information:
TSCA (Toxic Substances Control Act): Listed
RTECS No.: VV2750000
Transportation Classification: UN 3276, Nitriles, toxic, n.o.s. (cyanide-containing organosilicon compounds)