Trimethylsilylacetylene on:
[Wikipedia]
[Google]
[Amazon]
Trimethylsilylacetylene is the organosilicon compound with the formula . A colorless liquid, "tms acetylene", as it is also called, is used as a source of
anion
An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by conven ...
in organic synthesis
Organic synthesis is a branch of chemical synthesis concerned with the construction of organic compounds. Organic compounds are molecules consisting of combinations of covalently-linked hydrogen, carbon, oxygen, and nitrogen atoms. Within the gen ...
.
Use
Trimethylsilylacetylene is used in Sonogashira couplings as the equivalent ofacetylene
Acetylene (Chemical nomenclature, systematic name: ethyne) is a chemical compound with the formula and structure . It is a hydrocarbon and the simplest alkyne. This colorless gas is widely used as a fuel and a chemical building block. It is u ...
. Using this protected alkyne, as opposed to acetylene itself, prevents further coupling reactions. The trimethylsilyl 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 minus;Si(CH3)3 which is in turn bonded to the rest of a molecule. This structural group i ...
can then be cleaved off with TBAF or DBU to form phenylacetylene derivatives. Trimethylsilylacetylene is also used to synthesize diphenylacetylene derivatives in a one-pot Sonogashira coupling, in which the phenylacetylene derivative reacts with a second aryl halide after in-situ deprotection. A less expensive alternative reagent is 2-methylbut-3-yn-2-ol
2-Methylbut-3-yn-2-ol is the organic compound with the formula HC2C(OH)Me2 (Me = CH3). A colorless liquid, it is classified as an alkynyl alcohol.
Preparation and use
It arises from the condensation of acetylene and acetone. The addition can be p ...
, which after alkynylation is deprotected with base.
Trimethylsilylacetylene is commercially available. It may also be prepared in a manner similar to other silyl compounds: deprotonation of acetylene with a Grignard reagent
Grignard reagents or Grignard compounds are chemical compounds with the general formula , where X is a halogen and R is an organic group, normally an alkyl or aryl. Two typical examples are methylmagnesium chloride and phenylmagnesium bromi ...
, followed by reaction with trimethylsilyl chloride.
Trimethylsilylacetylene is a precursor to 1,4-bis(trimethylsilyl)buta-1,3-diyne, a protected form of 1,3-butadiyne.
History
Trimethylsilylacetylene was first synthesized in 1959 by Heinz Günter Viehe. He reduced chloro(trimethylsilyl)acetylene by reaction with phenyllithium indiethyl ether
Diethyl ether, or simply ether, is an organic compound with the chemical formula , sometimes abbreviated as . It is a colourless, highly Volatility (chemistry), volatile, sweet-smelling ("ethereal odour"), extremely flammable liquid. It belongs ...
and proceeded with subsequent hydrolysis.{{citation, surname1=H. G. Viehe, periodical=Chemische Berichte
''Chemische Berichte'' (usually abbreviated as ''Ber.'' or ''Chem. Ber.'') was a German-language scientific journal of all disciplines of chemistry founded in 1868. It was one of the oldest scientific journals in chemistry, until it merged with ' ...
, title=Heterosubstituierte Acetylene, III. Nucleophile Substitutionen und Halogen-Metall-Austauschreaktionen an Dreifachbindungen, volume=92, issue=12, at=pp. 3064–3075, date=1959, language=German, doi=10.1002/cber.19590921209
References