Trimethylsilyl iodide

Trimethylsilyl iodide
Names
	IUPAC name Iodo(trimethyl)silane
Identifiers
CAS Number	16029-98-4;
3D model (JSmol)	Interactive image;
ChemSpider	76879;
ECHA InfoCard	100.036.503
PubChem CID	85247;
CompTox Dashboard (EPA)	DTXSID4065997 ;
	InChI InChI=1S/C3H9ISi/c1-5(2,3)4/h1-3H3 Key: CSRZQMIRAZTJOY-UHFFFAOYSA-N; InChI=1/C3H9ISi/c1-5(2,3)4/h1-3H3 Key: CSRZQMIRAZTJOY-UHFFFAOYAB;
	SMILES I[Si](C)(C)C;
Properties
Chemical formula	C3H9ISi
Molar mass	200.094 g·mol−1
Density	1.406 g/mL at 25 °C
Boiling point	106 °C (223 °F; 379 K)
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Trimethylsilyl iodide, (CH₃)₃SiI, or iodotrimethylsilane, is an organosilicon compound. It is a colorless, volatile liquid at room temperature.

Preparation

Trimethylsilyl iodide may be prepared by the oxidative cleavage of hexamethyldisilane by iodine,^[1] or by the cleavage of hexamethyldisiloxane with aluminium triiodide.^[1]^[2]

TMS-TMS + I₂ → 2 TMSI (TMS = (CH₃)₃Si)

TMS-O-TMS + AlI₃ → 2 TMSI + "AlIO"

Applications

Trimethylsilyl iodide is used to introduce the trimethylsilyl group onto alcohols (ROH):

ROH + TMSI → RO(TMS) + HI

This type of reaction may be useful for gas chromatography analysis; the resultant silyl ether is more volatile than the underivatized original materials.^[3]

For the preparation of bulk trimethylsilylated material, trimethylsilyl chloride may be preferred due to its lower cost.

References

^ ^a ^b Olah, G.; Narang, S.C. (1982). "Iodotrimethylsilane—a versatile synthetic reagent". Tetrahedron. 38 (15): 2225. doi:10.1016/0040-4020(82)87002-6.{{cite journal}}: CS1 maint: multiple names: authors list (link)
^ Michael E. Jung; Mark A. Lyster (1988). "Cleavage of Methyl Ethers with Iodotrimethylsilane: Cyclohexanol from Cyclohexyl Methyl Ether". Organic Syntheses; Collected Volumes, vol. 6, p. 353.
^ http://www.chem.agilent.com/Library/applications/gcms59_opiates_urine.pdf

[olah-1] Olah, G.; Narang, S.C. (1982). "Iodotrimethylsilane—a versatile synthetic reagent". Tetrahedron. 38 (15): 2225. doi:10.1016/0040-4020(82)87002-6.{{cite journal}}: CS1 maint: multiple names: authors list (link)

[2] Michael E. Jung; Mark A. Lyster (1988). "Cleavage of Methyl Ethers with Iodotrimethylsilane: Cyclohexanol from Cyclohexyl Methyl Ether". Organic Syntheses; Collected Volumes, vol. 6, p. 353.

[3] ttp://www.chem.agilent.com/Library/applications/gcms59_opiates_urine.pdf

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