Methyltrimethoxysilane

Methyltrimethoxysilane
Names
	Preferred IUPAC name Trimethoxy(methyl)silane
	Other names MTM, Trimethoxymethylsilane
Identifiers
CAS Number	1185-55-3 ;
3D model (JSmol)	Interactive image;
ChemSpider	13803;
ECHA InfoCard	100.013.350
PubChem CID	14456;
UNII	0HI0D71MCI ;
CompTox Dashboard (EPA)	DTXSID3027370 ;
	InChI InChI=1S/C4H12O3Si/c1-5-8(4,6-2)7-3/h1-4H3 Key: BFXIKLCIZHOAAZ-UHFFFAOYSA-N; InChI=1/C4H12O3Si/c1-5-8(4,6-2)7-3/h1-4H3 Key: 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

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

Methyltrimethoxysilane is usually prepared from methyltrichlorosilane and methanol:

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

Alcoholysis of alkylchlorosilanes typically proceeds via an S_N2 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 C_3v 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]

References

^ ^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.
^ 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.
^ Stephan, Pawlenko (1986). Organosilicon Chemistry. Berlin: Walter de Gruyter. ISBN 9780899252025.
^ 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.

[Brinker-1] 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.

[1]

[2]

[3]

[4]

Preparation, structure and reactivity

See also

References