Allyltrimethylsilan Chemische Eigenschaften,Einsatz,Produktion Methoden
R-Sätze Betriebsanweisung:
R11:Leichtentzündlich.
R36/37/38:Reizt die Augen, die Atmungsorgane und die Haut.
S-Sätze Betriebsanweisung:
S16:Von Zündquellen fernhalten - Nicht rauchen.
S26:Bei Berührung mit den Augen sofort gründlich mit Wasser abspülen und Arzt konsultieren.
S36:DE: Bei der Arbeit geeignete Schutzkleidung tragen.
S23:Gas/Rauch/Dampf/Aerosol nicht einatmen(geeignete Bezeichnung(en) vom Hersteller anzugeben).
S33:Maßnahmen gegen elektrostatische Aufladungen treffen.
S7/9:Behälter dicht geschlossen an einem gut gelüfteten Ort aufbewahren.
Chemische Eigenschaften
clear colourless liquid
Verwenden
Allyltrimethylsilane is a general reagent to introduce allyl groups across acid chlorides, aldehydes, ketones, iminium ions, enones, and for cross-coupling with other carbon electrophiles. It is used as a reagent in Hosomi?Sakurai reaction.
synthetische
Allyltrimethylsilane is synthesized by the reaction of trimethylchlorosilane and allylmagnesium bromide.
Application
Allyltrimethylsilane is used in the allylation of aldehydes, imines, allylic and benzylic alcohols, and chiral α-keto-amides that are derived from (S)-proline esters.
Reaktionen
Allyltrimethylsilane is involved as a reactant in Hosomi Sakurai reaction for allylation in the presence of Lewis acid. For example, it reacts with cyclohexanone to get 1-allylcyclohexanol. It acts as a nucleophile and is involved in Carbon-Ferrier rearrangement.
As a Carbon Nucleophile in Lewis Acid-Catalyzed Reactions.
Allyltrimethylsilane is an alkene some 10 times more nucleophilic than propene, as judged by its reactions with diarylmethyl cations.It reacts with a variety of cationic carbon electrophiles, usually prepared by coordination of a Lewis acid to a functional group, but also by chemical or electrochemical oxidation,or by irradiation in the presence of 9,10- dicyanoanthracene.
carbon to give an intermediate cation, and the silyl group is lost to create a double bond at the other terminus. Among the more straightforward electrophiles are acid chlorides (eq 1).
As a Carbon Nucleophile in Fluoride Ion-Catalyzed Reactions.
The reactions with aldehydes, ketones (eq 23),54 and α,β-unsaturated esters (eq 24)55 can also be catalyzed by fluoride ion, usually introduced as tetra-n-butylammonium fluoride (TBAF), or other silicophilic ions such as alkoxide. These reactions produce silyl ether intermediates, which are usually hydrolyzed before workup. The stereochemistry of attack on chiral ketones can sometimes be different for the Lewis acid- and fluoride ion-catalyzed reactions.
Other Reactions.
Allyltrimethylsilane reacts with some highly electrophilic alkenes, carbonyl compounds, azo compounds, and singlet oxygen to a greater or lesser extent in ene reactions that do not involve the loss of the silyl group, and hence give vinylsilanes in a solvent-dependent reaction.
läuterung methode
Fractionate it through an efficient column at atmospheric pressure. If impure, dissolve it in THF, shake it with H2O (2x), dry (Na2SO4), filter and fractionate it. [Cudlin & Chvalovsky′ Collect Czech Chem Commun 27 1658 1962, Beilstein 4 IV 3927.]
Allyltrimethylsilan Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte