Trimethylsilyl chloride, also known as chlorotrimethylsilane is a silyl halide, with a variety of different uses in chemistry. It has the formula (CH₃)₃SiCl, and under standard conditions it is a colourless liquid, which is stable in the absence of water. It can be prepared from silicon tetrachloride

Silicon tetrachloride

Silicon tetrachloride is the inorganic compound with the formula SiCl4. It is a colourless volatile liquid that fumes in air. It is used to produce high purity silicon and silica for commercial applications.-Preparation:...

 by nucleophillic substitution of three of the chloride groups with a nucleophillic methyl source such as methyllithium, however the compound is readily available commercially.

Uses

Trimethylsilyl chloride has variety of uses in chemistry, both as a source of the trimethylsilyl

Trimethylsilyl

A trimethylsilyl group is a functional group in organic chemistry. This group consists of three methyl groups bonded to a silicon atom [−Si3], which is in turn bonded to the rest of a molecule...

 group, and as an anhydrous source of chlorides.
Functional groups such as alcohols and amine

Amine

Amines are organic compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are derivatives of ammonia, wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group. Important amines include amino acids, biogenic amines,...

s readily undergo reaction with trimethylsilyl chloride, giving trimethylsilyl

Trimethylsilyl

A trimethylsilyl group is a functional group in organic chemistry. This group consists of three methyl groups bonded to a silicon atom [−Si3], which is in turn bonded to the rest of a molecule...

 ether

Ether

Ethers are a class of organic compounds that contain an ether group — an oxygen atom connected to two alkyl or aryl groups — of general formula R–O–R'. A typical example is the solvent and anesthetic diethyl ether, commonly referred to simply as "ether"...

s and trimethylsilyl

Trimethylsilyl

A trimethylsilyl group is a functional group in organic chemistry. This group consists of three methyl groups bonded to a silicon atom [−Si3], which is in turn bonded to the rest of a molecule...

 amine

Amine

Amines are organic compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are derivatives of ammonia, wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group. Important amines include amino acids, biogenic amines,...

s. These new groups can be used as protecting group

Protecting group

A protecting group or protective group is introduced into a molecule by chemical modification of a functional group in order to obtain chemoselectivity in a subsequent chemical reaction...

s for the original functional group, however the lability

Lability

Lability refers to something that is constantly undergoing change or something that is likely to undergo change.-Chemistry:The term is used to describe a relatively unstable and transient chemical species...

 of the trimethylsilyl

Trimethylsilyl

A trimethylsilyl group is a functional group in organic chemistry. This group consists of three methyl groups bonded to a silicon atom [−Si3], which is in turn bonded to the rest of a molecule...

 group restricts their utility. Trimethylsilyl

Trimethylsilyl

A trimethylsilyl group is a functional group in organic chemistry. This group consists of three methyl groups bonded to a silicon atom [−Si3], which is in turn bonded to the rest of a molecule...

ation can also be used to increase the volatility of a compound, enabling gas chromatography of normally non-volatile substances such as glucose

Glucose

Glucose is a simple sugar and an important carbohydrate in biology. Cells use it as the primary source of energy and a metabolic intermediate...

. Trimethylsilyl chloride also reacts with metal acetylides to give trimethylsilyl alkynes, which are useful protected forms of alkynes.

The reaction of trimethylsilyl chloride with alcohols gives rise to an equivalent of hydrogen chloride

Hydrogen chloride

The compound hydrogen chloride has the formula HCl. At room temperature, it is a colorless gas, which forms white fumes of hydrochloric acid upon contact with atmospheric humidity. Hydrogen chloride gas and hydrochloric acid are important in technology and industry...

. This reaction can be exploited to create anhydrous

Anhydrous

As a general term, a substance is said to be anhydrous if it contains no water. The way of achieving the anhydrous form differs from one substance to another...

 solutions of hydrochloric acid

Hydrochloric acid

Hydrochloric acid is a solution of hydrogen chloride in water, that is a highly corrosive, strong mineral acid with many industrial uses. It is found naturally in gastric acid....

 in alcohols, which find use in the mild synthesis of ester

Ester

Esters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are usually derived from an inorganic acid or organic acid in which at least one -OH group is replaced by an -O-alkyl group, and most commonly from carboxylic acids and...

s and acetal

Acetal

An acetal is a molecule with two single-bonded oxygen atoms attached to the same carbon atom.Traditional usages distinguish ketals from acetals...

s from carboxylic acid

Carboxylic acid

Carboxylic acids are organic acids characterized by the presence of at least one carboxyl group. The general formula of a carboxylic acid is R-COOH, where R is some monovalent functional group...

s and ketone

Ketone

In organic chemistry, a ketone is an organic compound with the structure RCR', where R and R' can be a variety of atoms and groups of atoms. It features a carbonyl group bonded to two other carbon atoms. Many ketones are known and many are of great importance in industry and in biology...

s respectively.

In the presence of triethylamine

Triethylamine

Triethylamine is the chemical compound with the formula N3, commonly abbreviated Et3N. It is also abbreviated TEA, yet this abbreviation must be used carefully to avoid confusion with triethanolamine, for which TEA is also a common abbreviation....

 and lithium diisopropylamide

Lithium diisopropylamide

Lithium diisopropylamide is the chemical compound with the formula [2CH]2NLi. Generally abbreviated LDA, it is a strong base used in organic chemistry for the deprotonation of weakly acidic compounds. The reagent has been widely accepted because it is soluble in non-polar organic solvents and it...

, enol

Enol

Enols are alkenes with a hydroxyl group affixed to one of the carbon atoms composing the double bond. Alkenes with a hydroxyl group on both sides of the double bond are called enediols. Deprotonated anions of enols are called enolates...

isable aldehyde

Aldehyde

An aldehyde is an organic compound containing a formyl group. This functional group, with the structure R-CHO, consists of a carbonyl center bonded to hydrogen and an R group....

s, ketone

Ketone

In organic chemistry, a ketone is an organic compound with the structure RCR', where R and R' can be a variety of atoms and groups of atoms. It features a carbonyl group bonded to two other carbon atoms. Many ketones are known and many are of great importance in industry and in biology...

s and ester

Ester

Esters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are usually derived from an inorganic acid or organic acid in which at least one -OH group is replaced by an -O-alkyl group, and most commonly from carboxylic acids and...

s are converted to trimethylsilyl

Trimethylsilyl

A trimethylsilyl group is a functional group in organic chemistry. This group consists of three methyl groups bonded to a silicon atom [−Si3], which is in turn bonded to the rest of a molecule...

 enol ether

Enol ether

An enol ether is an alkene with an alkoxy substituent. The general structure is R_1R_2C=CR_3-O-R_4 with R an alkyl or an aryl group. Enol ethers and enamines are so-called activated alkenes or electron rich alkenes because the oxygen atom donates electrons to the double bond by forming a resonance...

s. Despite their hydrolytic instability, these compounds have found wide application in organic chemistry; oxidation  of the double bond

Double bond

A double bond in chemistry is a chemical bond between two chemical elements involving four bonding electrons instead of the usual two. The most common double bond, that between two carbon atoms, can be found in alkenes. Many types of double bonds between two different elements exist, for example in...

 by epoxidation or dihydroxylation can be used to return the original carbonyl

Carbonyl

In organic chemistry, a carbonyl group is a functional group composed of a carbon atom double-bonded to an oxygen atom: C=O. It is common to several classes of organic compounds, as part of many larger functional groups....

 group with an alcohol

Alcohol

In chemistry, an alcohol is an organic compound in which the hydroxy functional group is bound to a carbon atom. In particular, this carbon center should be saturated, having single bonds to three other atoms....

 group at the alpha carbon. The trimethylsilyl

Trimethylsilyl

A trimethylsilyl group is a functional group in organic chemistry. This group consists of three methyl groups bonded to a silicon atom [−Si3], which is in turn bonded to the rest of a molecule...

 enol ether

Enol ether

An enol ether is an alkene with an alkoxy substituent. The general structure is R_1R_2C=CR_3-O-R_4 with R an alkyl or an aryl group. Enol ethers and enamines are so-called activated alkenes or electron rich alkenes because the oxygen atom donates electrons to the double bond by forming a resonance...

s can also be used as masked enolate equivalents in the Mukaiyama aldol addition

Mukaiyama aldol addition

The Mukaiyama aldol addition is an organic reaction and a type of aldol reaction between a silyl enol ether and an aldehyde catalyzed by a Lewis acid. This choice of reactants allows for a crossed aldol reaction between an aldehyde and a ketone or a different aldehyde without self-condensation of...

.

Trimethylsilyl chloride can also be used as a starting material to prepare other trimethylsilyl halides and pseudohalides, such as:

• Trimethylsilyl fluoride
• Trimethylsilyl bromide
• Trimethylsilyl iodide
• Trimethylsilyl cyanide
  Trimethylsilyl cyanide
  Trimethylsilyl cyanide is the chemical compound with the formula 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...
  
  
• Trimethylsilyl azide
  Trimethylsilyl azide
  Trimethylsilyl azide is a chemical compound used as a reagent in organic chemistry.-Preparation:Trimethylsilyl azide is commercially available. It may be prepared by the reaction of trimethylsilyl chloride and sodium azide:-Applications:...
  
  
• Trimethylsilyl trifluoromethanesulfonate (TMSOTf)

These compounds are produced by an exchange reaction between trimethylsilyl chloride and a salt of the (pseudo)halide (MX):

MX + Me₃Si-Cl → MCl + Me₃Si-X

Trimethylsilyl chloride is also used to silanize laboratory glassware

Laboratory glassware

Laboratory glassware refers to a variety of equipment, traditionally made of glass, used for scientific experiments and other work in science, especially in chemistry and biology laboratories...

, making the surfaces more lipophilic

Lipophilic

Lipophilicity, , refers to the ability of a chemical compound to dissolve in fats, oils, lipids, and non-polar solvents such as hexane or toluene. These non-polar solvents are themselves lipophilic — the axiom that like dissolves like generally holds true...

.