Bis(trimethylsilyl)acetamide

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Bis(trimethylsilyl)acetamide
Bis(trimethylsilyl)acetamide.svg
Bis(trimethylsilyl)acetamide-3D.png
Names
Preferred IUPAC name
Trimethylsilyl N-(trimethylsilyl)ethanecarboximidate
Other names
N,O-Bis(trimethylsilyl)acetamide
Identifiers
3D model (JSmol)
AbbreviationsBSA
1306669
ChemSpider
ECHA InfoCard 100.030.799 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 233-892-7
MeSH N,O-bis(trimethylsilyl)acetamide
PubChem CID
RTECS number
  • AK3000000
UNII
UN number 2920
  • InChI=1S/C8H21NOSi2/c1-8(9-11(2,3)4)10-12(5,6)7/h1-7H3
    Key: SIOVKLKJSOKLIF-UHFFFAOYSA-N
  • InChI=1/C8H21NOSi2/c1-8(9-11(2,3)4)10-12(5,6)7/h1-7H3/b9-8+
  • CC(=N[Si](C)(C)C)O[Si](C)(C)C
  • CC(O[Si](C)(C)C)=N[Si](C)(C)C
Properties
C8H21NOSi2
Molar mass 203.432 g·mol−1
AppearanceLiquid
Density 0.832 g cm−3
Melting point 24 °C (75 °F; 297 K)
Boiling point 71 to 73 °C (160 to 163 °F; 344 to 346 K) at 35mmHg
Hazards
GHS labelling:
GHS-pictogram-flamme.svg GHS-pictogram-acid.svg GHS-pictogram-exclam.svg
Danger
H226, H302, H314
P210, P233, P240, P241, P242, P243, P260, P264, P270, P280, P301+P312, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P310, P321, P330, P363, P370+P378, P403+P235, P405, P501
Related compounds
Related Amides
Dimethylacetamide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Bis(trimethylsilyl)acetamide (BSA) is an organosilicon compound with the formula MeC(OSiMe3)NSiMe3 (Me = CH3). It is a colorless liquid that is soluble in diverse organic solvents, but reacts rapidly with moisture and solvents containing OH and NH groups. It is used in analytical chemistry to increase the volatility of analytes, e.g., for gas chromatography. [1] It is also used to introduce the trimethylsilyl protecting group in organic synthesis. [2] A related reagent is N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA).

Synthesis and reactions

BSA is prepared by treating acetamide with trimethylsilyl chloride in the presence of a base (Me = CH3, Et = C2H5): [2]

MeC(O)NH2 + 2 SiMe3Cl + 2 Et3N→ MeC(OSiMe3)NSiMe3 + 2 Et3NHCl

The reaction of BSA with alcohols gives the corresponding trimethylsilyl ether, together with acetamide as a byproduct (Me = CH3): [3]

2 ROH + MeC(OSiMe3)NSiMe3 → MeC(O)NH2 + 2 ROSiMe3

Related Research Articles

Acetamide (systematic name: ethanamide) is an organic compound with the formula CH3CONH2. It is derived from acetic acid. It finds some use as a plasticizer and as an industrial solvent. The related compound N,N-dimethylacetamide (DMA) is more widely used, but it is not prepared from acetamide. Acetamide can be considered an intermediate between acetone, which has two methyl (CH3) groups either side of the carbonyl (CO), and urea which has two amide (NH2) groups in those locations. Acetamide is also a naturally occurring mineral with the IMA symbol: Ace.

<span class="mw-page-title-main">DABCO</span> Chemical compound

DABCO (1,4-diazabicyclo[2.2.2]octane), also known as triethylenediamine or TEDA, is a bicyclic organic compound with the formula N2(C2H4)3. This colorless solid is a highly nucleophilic tertiary amine base, which is used as a catalyst and reagent in polymerization and organic synthesis.

<span class="mw-page-title-main">Triphenylphosphine</span> Chemical compound

Triphenylphosphine (IUPAC name: triphenylphosphane) is a common organophosphorus compound with the formula P(C6H5)3 and often abbreviated to PPh3 or Ph3P. It is widely used in the synthesis of organic and organometallic compounds. PPh3 exists as relatively air stable, colorless crystals at room temperature. It dissolves in non-polar organic solvents such as benzene and diethyl ether.

<span class="mw-page-title-main">Trimethylsilyl group</span> Functional group

A trimethylsilyl group (abbreviated TMS) is a functional group in organic chemistry. This group consists of three methyl groups bonded to a silicon atom [−Si(CH3)3], which is in turn bonded to the rest of a molecule. This structural group is characterized by chemical inertness and a large molecular volume, which makes it useful in a number of applications.

<span class="mw-page-title-main">Sodium bis(trimethylsilyl)amide</span> Chemical compound

Sodium bis(trimethylsilyl)amide is the organosilicon compound with the formula NaN(Si 3)2. This species, usually called NaHMDS, is a strong base used for deprotonation reactions or base-catalyzed reactions. Its advantages are that it is commercially available as a solid and it is soluble not only in ethers, such as THF or diethyl ether, but also in aromatic solvents, like benzene and toluene by virtue of the lipophilic TMS groups.

<span class="mw-page-title-main">Trimethylsilyl chloride</span> Chemical compound

Trimethylsilyl chloride, also known as chlorotrimethylsilane is an organosilicon compound (silyl halide), with the formula (CH3)3SiCl, often abbreviated Me3SiCl or TMSCl. It is a colourless volatile liquid that is stable in the absence of water. It is widely used in organic chemistry.

<span class="mw-page-title-main">Trimethylsilyl cyanide</span> Chemical compound

Trimethylsilyl cyanide is the chemical compound with the formula (CH3)3SiCN. This volatile liquid consists of a cyanide group, that is CN, attached to a trimethylsilyl group. The molecule is used in organic synthesis as the equivalent of hydrogen cyanide. It is prepared by the reaction of lithium cyanide and trimethylsilyl chloride:

Bis(trimethylsilyl)amine (also known as hexamethyldisilazane and HMDS) is an organosilicon compound with the molecular formula [(CH3)3Si]2NH. The molecule is a derivative of ammonia with trimethylsilyl groups in place of two hydrogen atoms. An electron diffraction study shows that silicon-nitrogen bond length (173.5 pm) and Si-N-Si bond angle (125.5°) to be similar to disilazane (in which methyl groups are replaced by hydrogen atoms) suggesting that steric factors are not a factor in regulating angles in this case. This colorless liquid is a reagent and a precursor to bases that are popular in organic synthesis and organometallic chemistry. Additionally, HMDS is also increasingly used as molecular precursor in chemical vapor deposition techniques to deposit silicon carbonitride thin films or coatings.

<span class="mw-page-title-main">Hexamethyldisiloxane</span> Chemical compound

Hexamethyldisiloxane (HMDSO or MM) is an organosilicon compound with the formula O[Si(CH3)3]2. This volatile colourless liquid is used as a solvent and as a reagent in organic synthesis. It is prepared by the hydrolysis of trimethylsilyl chloride. The molecule is the protypical disiloxane and resembles a subunit of polydimethylsiloxane.

<span class="mw-page-title-main">Bis(trimethylsilyl)sulfide</span> Chemical compound

Bis(trimethylsilyl) sulfide is the chemical compound with the formula ((CH3)3Si)2S. Often abbreviated (tms)2S, this colourless, vile-smelling liquid is a useful aprotic source of "S2−" in chemical synthesis.

<span class="mw-page-title-main">Trimethylsilyl azide</span> Chemical compound

Trimethylsilyl azide is the organosilicon compound with the formula (CH3)3SiN3. A colorless liquid, it is a reagent in organic chemistry, serving as the equivalent of hydrazoic acid.

<span class="mw-page-title-main">Tributyltin hydride</span> Chemical compound

Tributyltin hydride is an organotin compound with the formula (C4H9)3SnH. It is a colorless liquid that is soluble in organic solvents. The compound is used as a source of hydrogen atoms in organic synthesis.

<span class="mw-page-title-main">Lithium bis(trimethylsilyl)amide</span> Chemical compound

Lithium bis(trimethylsilyl)amide is a lithiated organosilicon compound with the formula LiN(Si(CH3)3)2. It is commonly abbreviated as LiHMDS or Li(HMDS) (lithium hexamethyldisilazide - a reference to its conjugate acid HMDS) and is primarily used as a strong non-nucleophilic base and as a ligand. Like many lithium reagents, it has a tendency to aggregate and will form a cyclic trimer in the absence of coordinating species.

<span class="mw-page-title-main">Diethylaminosulfur trifluoride</span> Chemical compound

Diethylaminosulfur trifluoride (DAST) is the organosulfur compound with the formula Et2NSF3. This liquid is a fluorinating reagent used for the synthesis of organofluorine compounds. The compound is colourless; older samples assume an orange colour.

Silylation is the introduction of one or more (usually) substituted silyl groups (R3Si) to a molecule. Silylations are core methods for production of organosilicon chemistry. Silanization involves similar methods but usually refers to attachment of silyl groups to solids.

<span class="mw-page-title-main">BSTFA</span> Chemical compound

N,O-Bis(trimethylsilyl)trifluoroacetamide (BSTFA) is an organosilicon compound. It is a colorless liquid that is very sensitive to traces of water or alcohols.

<span class="mw-page-title-main">Metal bis(trimethylsilyl)amides</span>

Metal bis(trimethylsilyl)amides are coordination complexes composed of a cationic metal with anionic bis(trimethylsilyl)amide ligands and are part of a broader category of metal amides.

<span class="mw-page-title-main">Metal amides</span>

Metal amides (systematic name metal azanides) are a class of coordination compounds composed of a metal center with amide ligands of the form NR2. Amide ligands have two electron pairs available for bonding. In principle, they can be terminal or bridging. In these two examples, the dimethylamido ligands are both bridging and terminal:

<span class="mw-page-title-main">Tris(trimethylsilyl)amine</span> Chemical compound

Tris(trimethylsilyl)amine is the simplest tris(trialkylsilyl)amine which are having the general formula (R3Si)3N, in which all three hydrogen atoms of the ammonia are replaced by trimethylsilyl groups (-Si(CH3)3). Tris(trimethylsilyl)amine has been for years in the center of scientific interest as a stable intermediate in chemical nitrogen fixation (i. e. the conversion of atmospheric nitrogen N2 into organic substrates under normal conditions).

<span class="mw-page-title-main">(Trimethylsilyl)methyllithium</span> Chemical compound

(Trimethylsilyl)methyllithium is classified both as an organolithium compound and an organosilicon compound. It has the empirical formula LiCH2Si(CH3)3, often abbreviated LiCH2tms. It crystallizes as the hexagonal prismatic hexamer [LiCH2tms]6, akin to some polymorphs of methyllithium. Many adducts have been characterized including the diethyl ether complexed cubane [Li43-CH2tms)4(Et2O)2] and [Li2(μ-CH2tms)2(tmeda)2].

References

  1. Blau, Karl; J. M. Halket (1993). Handbook of Derivatives for Chromatography (2nd ed.). John Wiley & Sons. ISBN   0-471-92699-X.
  2. 1 2 Harry Heaney, Jian Cui, “N,O-Bis(trimethylsilyl)acetamide” Encyclopedia of Reagents for Organic Synthesis Copyright © 2007 John Wiley & Sons. doi : 10.1002/047084289X.rb208.pub2.
  3. Young, Steven D.; Buse, Charles T.; Heathcock, Clayton H. (1985). "2-Methyl-2-(Trimethylsiloxy)pentan-3-one". Organic Syntheses. 63: 79. doi:10.15227/orgsyn.063.0079.