bob000555 - 18-4-2007 at 12:19
Can you prepare sodium acetylide(which should be a fairly powerful explosive) by simply mixing CaC2 and NaOH in a non-aqueous solvent e.g. ethanol or
liquid ammonia? Could you also make ammonium acetylide by mixing NH4OH with CaC2 in a solvent?
DeAdFX - 18-4-2007 at 14:21
http://www.cem.msu.edu/~reusch/VirtualText/addyne1.htm
... Use google in the future. scroll down ~3/4 of the way.
franklyn - 18-4-2007 at 16:15
It's not explosive although it is a strong reducer but except as a reagent in
synthesis offers no benefit over other far cheaper materials such as CaC2.
Hydroxyl in ether will protonate the acetylide ; you need a much stronger base
such as sodium amide NaNH2. See here '"Consider the solvent ammonia"
http://www.lauher.com/che142/acidbase.pdf
Sodium amide itself is made by heating sodium in anhydrous ammonia. See
http://www.ch.ic.ac.uk/local/organic/15.html
Sodium acetylide is made directly from acetylene passed into sodium amide
NaNH2 dissolved in liquid ammonia.
NaNH2 + NH3 + HCCH ==> HCCNa + 2NH3
A free acetylide ion has no known solvation. The metathesis you propose
would have to take place in a molten state possibly in a flouride salt as is
used in the Hall process for the refinement of aluminum.
The acetylides of copper and silver are touch sensitive primary explosives.
Cuprous acetylide is formed from acetylene passed into an ammoniacal solution
of cuprous chloride.
Cu2Cl2 + 2 NH4OH + HCCH ==> CuCCCu + 2 NH4Cl + 2 H2O
Silver acetylide is formed from acetylene passed into an ammoniacal solution
of silver nitrate.
2AgNO3 + 2 NH4OH + HCCH ==> AgCCAg + 2 NH4NO3
Many organic acetylides , propyne for one will polymerize explosively. It can
be prepared from sodium acetylide in monobromomethane.
HCCNa + CH3I ==> HCCCH3 + NaI
Methyl acetylides are explosive when dry so great care should be taken in their
preparation. The metal acetylides can be destroyed when they are still wet
by warming with dilute acid which will regenerate the parent ethyne.
HCCNa + HNO3 ==> HCCH + NaNO3
http://www.ucc.ie/academic/chem/dolchem/html/dict/alkynes.ht...
.
[Edited on 5-1-2008 by franklyn]