Methyltrimethoxysilane (original) (raw)

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Methyltrimethoxysilane
Names
Preferred IUPAC name Trimethoxy(methyl)silane
Other namesMTM, Trimethoxymethylsilane
Identifiers
CAS Number 1185-55-3 checkY
3D model (JSmol) Interactive image
ChemSpider 13803
ECHA InfoCard 100.013.350 Edit this at Wikidata
PubChem CID 14456
UNII 0HI0D71MCI checkY
CompTox Dashboard (EPA) DTXSID3027370 Edit this at Wikidata
InChI InChI=1S/C4H12O3Si/c1-5-8(4,6-2)7-3/h1-4H3Key: BFXIKLCIZHOAAZ-UHFFFAOYSA-NInChI=1/C4H12O3Si/c1-5-8(4,6-2)7-3/h1-4H3Key: BFXIKLCIZHOAAZ-UHFFFAOYAM
SMILES CO[Si](C)(OC)OC
Properties
Chemical formula C4H12O3Si
Molar mass 136.222 g·mol−1
Appearance Colorless liquid
Density 0.955 g/cm3
Boiling point 102–104 °C (216–219 °F; 375–377 K)
Solubility in water hydrolysis
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Chemical compound

Methyltrimethoxysilane is an organosilicon compound with the formula CH3Si(OCH3)3. It is a colorless, free-flowing liquid. It is a crosslinker in the preparation of polysiloxane polymers.[1][2]

Preparation, structure and reactivity

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Methyltrimethoxysilane is usually prepared from methyltrichlorosilane and methanol:

CH3SiCl3 + 3 CH3OH → CH3Si(OCH3)3 + 3 HCl

Alcoholysis of alkylchlorosilanes typically proceeds via an SN2 mechanism. Inversion of the configuration is favored during nucleophilic attack when displacing good leaving groups, such as chloride.[3] In contrast, displacement of poor leaving groups, such as alkoxide, retention is favored.[4]

Methyltrimethoxysilane is tetrahedral and is often described as sp3 hybridized. It has idealized C3v point symmetry.

Hydrolysis of MTM proceeds both under acidic and basic conditions. Under acid conditions, rates of successive hydrolyses for methyltrimethoxysilane decreases with each step. Under basic condition the opposite is true.[1]

  1. ^ a b Brinker, C.J. (1988). "Hydrolysis and condensation of silicates: Effects on structure" (PDF). Journal of Non-Crystalline Solids. 100: 31. Bibcode:1988JNCS..100...31B. doi:10.1016/0022-3093(88)90005-1.
  2. ^ Kuroda, Kazuyuki; Shimojima, Atsushi; Kawahara, Kazufumi; Wakabayashi, Ryutaro; Tamura, Yasuhiro; Asakura, Yusuke; Kitahara, Masaki (2014). "Utilization of Alkoxysilyl Groups for the Creation of Structurally Controlled Siloxane-Based Nanomaterials". Chemistry of Materials. 26: 211. doi:10.1021/cm4023387.
  3. ^ Stephan, Pawlenko (1986). Organosilicon Chemistry. Berlin: Walter de Gruyter. ISBN 9780899252025.
  4. ^ Colvin, Ernest W. (1981). Silicon in Organic Synthesis. Butterworth and Co Ltd. doi:10.1016/c2013-0-04155-2. ISBN 978-0-408-10831-7.