Trimethylsilylacetylene
- CAS number
- 1066-54-2
- Molecular formula
- C5H10Si
- Molecular weight
- 98.22 g/mol
- Standard packing
- 1kg / 25kg / 100kg
Trimethylsilylacetylene is an alkyne entry under CAS 1066-54-2: C5H10Si, 98.22 g/mol, standard packing 1kg / 25kg / 100kg.
Because the alkyne hydrogen is acidic enough to deprotonate cleanly, this entry is usually the nucleophile in whichever step it appears in. The protecting group is the reason the entry exists: it is carried through the steps that would otherwise attack the group underneath, and removed when that group is wanted.
The formula C5H10Si resolves to 5 carbons with one silicon. Short-chain entries of this size are volatile enough that headspace and packing matter: the lot is shipped in sealed units and opened in a fume hood.
Where this entry sits in a route
Ethynyltrimethylsilane is the standard way to introduce a protected two-carbon unit. The TMS group keeps the alkyne from reacting at the terminal carbon during the coupling step, and is removed afterwards with fluoride or mild base. In practice it is charged in Sonogashira couplings where the free acetylene would be too volatile or too reactive to handle, and in the preparation of ethynyl ketones and ethynyl heteroaromatics where the TMS-protected intermediate is the isolable compound.
What the analysis covers
The lot is checked for residual trimethylsilyl chloride and for the disiloxane that forms if the material has been exposed to moisture. Both are visible on the GC trace, and both change the effective assay of the alkyne.
Handling and storage
Alkynes are held closed, dry and out of direct light; the silylated entries are also moisture sensitive and are packed under inert gas.
Ordering
The unit weights held are 1kg / 25kg / 100kg. A split shipment across two of those sizes is treated as one lot and one certificate. The certificate states identity, assay and the analytical method used; a tighter limit than the catalogue entry can be written into the lot specification.
Quotation questions for this entry
How is trimethylsilylacetylene handled on arrival?
It is a low-boiling, flammable liquid and is kept cold, closed and away from ignition sources. The container is allowed to reach room temperature before opening so that condensation does not carry water into the material.
Does the TMS group come off cleanly?
Yes. Fluoride sources and mild base both cleave it, and the choice depends on what else is in the molecule. The by-product is volatile, which is why the deprotection is usually a simple concentration rather than a chromatography step.
Is it available in multi-kilo quantities?
Yes. Standard packing runs to 100 kg and larger lots are quoted against a schedule rather than from stock.
What documentation comes with the lot?
A batch certificate of analysis stating identity and assay, a GHS safety data sheet, and a specification sheet for incoming inspection.
Other protected & silylated alkynes entries
| CAS | Compound | Formula | MW | Packing | Quote |
|---|---|---|---|---|---|
| 18180-30-8 | 2-((prop-2-yn-1-yloxy)Methyl)oxirane | C6H8O2 | 112.13 | 1kg / 25kg / 100kg | Request |
| 6089-04-9 | 2-Propynyl 2-pyranyl ether | C8H12O2 | 140.18 | 1kg / 25kg / 100kg | Request |
Ask about Trimethylsilylacetylene
The form below is pre-filled with this entry. Add the quantity, the specification you need to meet and the destination, and a written quotation follows within one business day.
| Entry | Trimethylsilylacetylene |
|---|---|
| CAS | 1066-54-2 |
| Typical lead time | Stock or 2–4 weeks |
| Documentation | COA, SDS, spec sheet |
Request a quotation
Trimethylsilylacetylene (1066-54-2)