74542-82-8

Basic information

• Product Name: 1-METHYL-1-(TRIMETHYLSILYL)ALLENE
• Synonyms: 1-METHYL-1-(TRIMETHYLSILYL)ALLENE;3-(Trimethylsilyl)-1,2-butadiene;3-(Trimethylsilyl)-1,2-butadiene 98%;Buta-2,3-Dien-2-Yl(Trimethyl)Silane
• CAS NO: 74542-82-8
• Molecular Formula: C₇H₁₄Si
• Molecular Weight: 126.27
• Product Categories: Allenes;Building Blocks;Organic Building Blocks;Building Blocks;Chemical Synthesis;Organic Building Blocks
• Mol File: 74542-82-8.mol
• Article Data: 4

Chemical Properties

• Boiling Point: 111-112 °C(lit.)
• Flash Point: 19 °F
• Appearance: /
• Density: 0.759 g/mL at 25 °C(lit.)
• Vapor Pressure: 21.7mmHg at 25°C
• Refractive Index: n20/D 1.444(lit.)
• Solubility: sol CH2Cl2, benzene, THF, Et2O, and most organic solvents.
• CAS DataBase Reference: 1-METHYL-1-(TRIMETHYLSILYL)ALLENE(CAS DataBase Reference)
• NIST Chemistry Reference: 1-METHYL-1-(TRIMETHYLSILYL)ALLENE(74542-82-8)
• EPA Substance Registry System: 1-METHYL-1-(TRIMETHYLSILYL)ALLENE(74542-82-8)

Safety Data

• Hazard Codes: F
• Statements: 11
• Safety Statements: 16
• RIDADR: UN 1993 3/PG 2
• WGK Germany: 3
• Hazardous Substances Data: 74542-82-8(Hazardous Substances Data)

Usage

Physical properties

bp 111 °C; bp 54–56 °C/90 mmHg

Uses

Different sources of media describe the Uses of 74542-82-8 differently. You can refer to the following data:
1. It is widely used as propargylic anion equivalents; three-carbon synthons for [3 + 2] annulations leading to five-membered compounds including cyclopentenes,4 dihydrofurans, pyrrolines, isoxazoles, furans, and azulenes.
2. 3-(Trimethylsilyl)-1,2-butadiene may be used for the synthesis of γ-(trimethylsilyl)allylborane.

Preparation

1-methyl-1-(trialkylsilyl)allenes can be conveniently prepared by the method of Vermeer. Silylsubstituted propargyl mesylates thus undergo SN2 displacement by the organocopper reagent generated from methylmagnesium chloride, copper(I) bromide, and lithium bromide 1-Methyl-1-(trimethylsilyl)allene is produced in 52% yield from commercially available (trimethylsilyl)propargyl alcohol in this fashion (eq 1). The t-butyldimethylsilyl and triisopropylsilyl analogs are synthesized by the same method in 90% and 58% yield, respectively. Propargyl alcohols bearing these and other trialkylsilyl groups can be prepared by treatment of propargyl alcohol with n-butyllithium and the appropriate trialkylsilyl chloride. Allenylsilanes bearing other C-1 substituents can be prepared in an analogous manner by using the appropriate Grignard reagents.

InChI:InChI=1/C7H14Si/c1-6-7(2)8(3,4)5/h1H2,2-5H3

Upstream product

• 5272-36-6 3-trimethylsilyl-2-propyn-1-ol 
• 71321-17-0 methanesulfonic acid 3-trimethylsilyl-propyn-2-ynyl ester 
• 676-58-4 methylmagnesium chloride 
• 75-77-4 chloro-trimethyl-silane 
• 3355-28-0 1-Bromo-2-butyne 
• 75-16-1 methylmagnesium bromide 

Downstream Products

• 1021325-82-5 (1R)-2,3,5,6-tetra-O-benzyl-1-benzyloxycarbonylamino-1-C-but-2-ynyl-1-deoxy-D-glucitol 
• 55172-29-7 thallium chloride 
• 1187852-64-7 C₁₄H₁₅BrO₂ 

Relevant articles and documents

Selective mono- and di-allylation and allenylation of chlorosilanes using indium

Allyl and allenyl groups have been introduced into silicon systems by the allylation and allenylation of chlorosilanes using allyl bromide or propargyl bromide with indium. The allylation of chlorosilanes afforded a variety of aryl, aralkyl, and alkenyl substituted allylsilanes. By applying this method, the reactions of 1-bromo-3-methylbut-2-ene, 3-bromo-2-methylprop-1-ene and 3-bromobut-1-ene with chlorosilanes also proceed smoothly to give regioselectively allylic rearrangement products in good yields. Mediated by indium, dichlorosilanes (R2SiCl2) and trichlorosilanes (RSiCl3) can either afford monoallylated silanes or diallylated silanes depending on the amount of allyl bromide and indium used.

Scope and Stereochemical Course of the Addition of (Trimethylsilyl)allenes to Ketones and Aldehydes. A Regiocontrolled Synthesis of Homopropargylic Alcohols

The reaction of (trimethylsilyl)allenes with aldehydes and ketones in the presence of titanium tetrachloride provides a regiocontrolled route to homopropargylic alcohols of a variety of substitution types.The addition of 1-alkyl-substituted (trimethylsilyl)allenes to carbonyl compounds furnishes the desired acetylenes directly, while reactions involving allenylsilanes 6,7, and 9 initially produce mixtures of acetylenes and (trimethylsilyl)vinyl chloride derivatives.Exposure of these mixtures to the action of potassium fluoride in dimethyl sulfoxide then generates the desired homopropargylic alcohols.The addition of the chiral allenylsilane 9 to achiral aldehydes has been found to proceed with modest (3-4:1) diastereoselectivity to produce mainly syn (erythro) homopropargylic alcohols.