70693-47-9

Basic information

• Product Name: 1,1,1,3,3-PENTAMETHYL-3-ACETOXYDISILOXANE
• Synonyms: pentamethyl-disiloxanoacetate;1,1,1,3,3-PENTAMETHYL-3-ACETOXYDISILOXANE;1-Acetoxy-1,1,3,3,3-pentamethyldisiloxane;pentamethyldisiloxanyl acetate;3-Acetoxy-1,1,1,3,3-pentamethyldisiloxane;1,1,3,3-Tetramethyl-2-oxa-1,3-disilabutan-1-ol acetate;Pentamethylpropanedisiloxane-1-ol acetate
• CAS NO: 70693-47-9
• Molecular Formula: C₇H₁₈O₃Si₂
• Molecular Weight: 206.39
• EINECS: 274-767-7
• Mol File: 70693-47-9.mol

Chemical Properties

• Boiling Point: 149 °C
• Flash Point: 40°C
• Appearance: /
• Density: 0.9
• Vapor Pressure: 4.03mmHg at 25°C
• Refractive Index: 1.3887
• CAS DataBase Reference: 1,1,1,3,3-PENTAMETHYL-3-ACETOXYDISILOXANE(CAS DataBase Reference)
• NIST Chemistry Reference: 1,1,1,3,3-PENTAMETHYL-3-ACETOXYDISILOXANE(70693-47-9)
• EPA Substance Registry System: 1,1,1,3,3-PENTAMETHYL-3-ACETOXYDISILOXANE(70693-47-9)

Safety Data

• Hazard Codes: C
• Statements: 10-34
• Safety Statements: 26-36/37/39-45
• RIDADR: UN 2924 3/PG 3
• TSCA: Yes
• Hazardous Substances Data: 70693-47-9(Hazardous Substances Data)

Usage

Uses

Used in Silicone Rubber and Sealants Industry:
1,1,1,3,3-PENTAMETHYL-3-ACETOXYDISILOXANE is used as a crosslinking agent for the production of silicone rubber and silicone sealants. It enhances the elasticity, durability, and stability of these materials, making them suitable for a wide range of applications.
Used in Waterproof Coatings and Textiles:
Leveraging its water-repellent properties, 1,1,1,3,3-PENTAMETHYL-3-ACETOXYDISILOXANE is used in the manufacturing of waterproof coatings and textiles. It provides a protective layer that repels water, making it ideal for outdoor gear, clothing, and other materials that require water resistance.
Used in Electronics Industry:
In the electronics industry, 1,1,1,3,3-PENTAMETHYL-3-ACETOXYDISILOXANE is utilized as an adhesive, anti-foaming agent, and mold release agent. Its properties contribute to improved manufacturing processes and the production of higher-quality electronic components.
Used in Automotive Industry:
Similarly, in the automotive industry, 1,1,1,3,3-PENTAMETHYL-3-ACETOXYDISILOXANE is employed for various applications, including as an adhesive, anti-foaming agent, and mold release agent. It aids in the production of components and the assembly process, ensuring better performance and durability of vehicles.
It is crucial to handle and store 1,1,1,3,3-PENTAMETHYL-3-ACETOXYDISILOXANE with care due to its flammability and potential to cause irritation upon contact with skin or eyes. Proper safety measures should be taken to mitigate any risks associated with its use.

InChI:InChI=1/C7H18O3Si2/c1-7(8)9-12(5,6)10-11(2,3)4/h1-6H3

Upstream product

• 2943-62-6 1-chloro-1,1,3,3,3-pentamethyldisiloxane 
• 64-19-7 acetic acid 
• 507-02-8 acetyl iodide 
• 107-51-7 octamethyltrisiloxabe 
• 1438-82-0 1,1,1,3,3-pentamethyl-1,3-disiloxane 
• 7440-05-3 palladium 
• 591-87-7 Allyl acetate 
• 108-24-7 acetic anhydride 

Downstream Products

• 556-70-7 docosamethyl-decasiloxane 
• 541-01-5 hexadecamethylheptasiloxane 

Relevant articles and documents

Ir-catalyzed hydrosilylation reaction of allyl acetate with octakis(dimethylsiloxy)octasilsesquioxane and related hydrosilanes

Hydrosilylation reaction of allyl acetate (AA) with octakis(dimethylsiloxy) octasilsesquioxane [(HSiMe2O)8(SiO1.5) 8] was efficiently catalyzed by chloro(1,5-cyclooctadiene)iridium(I) dimer [Ir(μ-Cl)(COD)]2

Acyl iodides in organic synthesis: IX. Cleavage of the Si-O-C and Si-O-Si moieties

Reactions of acyl iodides RCOI (R = Me, Ph) with organosilicon compounds involve cleavage of the Si-O-C and Si-O-Si fragments. Acetyl iodide reacts with alkyl(alkoxy)silanes with evolution of heat, and cleavage of the Si-O bond results in the formation of oligo-or polysiloxanes, alkyl iodides, and alkyl acetates. 1,3-Diacetoxytetramethyldisiloxane is formed in the reaction of acetyl iodide with dimethoxy(dimethyl)silane. Acyl iodides readily react with 1-ethoxysilatrane to give 1-acyloxysilatranes as a result of cleavage of the C-O bond. The reaction of acetyl iodide with hexaethyldisiloxane yields triethylsilyl acetate and triethyliodosilane, while in the reaction with octamethyltrisiloxane iodo(trimethyl)silane and dimethyl(trimethylsiloxy)silyl acetate are obtained. Nauka/Interperiodica 2007.

Kinetics of the condensation of oligosiloxanes containing acetoxyl and hydroxyl end groups catalyzed by uncharged nucleophiles in an acid-base inert solvent

Condensation of undecamethylpentasiloxane-1-ol (1) with 1-acetoxypentamethyldisiloxane (2) in methylene chloride in the presence of uncharged bases has been studied as a model for the coupling of acetoxyl and hydroxyl ended polydimethylsiloxane chains.Triethylamine acts not only as the acceptor of the acid released in the process but also as a Broensted base catalyst activating silanol group.However, weakly basic but strongly nucleophilic N-heterocycles such as 4-dimethylaminopyridine are more effective catalysts promoting the condensation by acting as nucleophiles to activate the acetoxysilane.

Method for preparing acetoxysiloxanes and organo(poly)siloxanes having halogen bonded to silicon

Organo(poly)siloxanes having halogen bonded directly to silicon, or acetoxysiloxanes are prepared by reacting organo(poly)siloxanes having hydrogen bonded directly to silicon, with an allyl compound in the presence of metallic palladium, ruthenium or rhodium, or an acetylacetone or phosphine complex, or compound containing palladium, ruthenium or rhodium in which the allyl compound is an allyl halide having 3 carbon atoms per molecule or allyl acetate.

REACTIONS IN THE CHLOROSILANE-SILANOL-SILOXANE SYSTEM

We obtained the first ?*-values and ES-values for siloxy groups by spectroscopic and kinetic methods.Detailed mechanistic investigations are performed on the hydrolysis of chlorosilanes, the cleavage of Si-O-Si bonds by HCl, and the substituent exchange reaction between silanols and chlorosilanes.

ZUR SYNTHESE VON SILOXANEN. II, STERISCHE SUBSTITUENTENKONSTANTEN FUER SILOXYRESTE

The acetolysis reactions of compounds of the type XSiMe2Cl (I) with acetic acid in the presence of acetic anhydride were studied kinetically by means of 1H NMR spectroscopy.We found these reactions exclusively influenced by steric effects (ρ=0).The steric susceptibility constant (δ) of the acetolysis reaction, using alkylchlorodimethylsilanes was found to be 1.3.In this investigation the Taft Es nvalues showed a better correlation than the Es(Si) values of Cartledge.From the rate constants of the acetolysis reactions with I (X=Cl, acetoxy or siloxy) we could then obtain for the first time Es values for Cl, acetoxy and a series of siloxy groups at silicon.