BromicAcid
International Hazard
Posts: 3227
Registered: 13-7-2003
Location: Wisconsin
Member Is Offline
Mood: Rock n' Roll
|
|
Trimethylsilyl nitrate; chlorotrimethylsilane; Trimethylsilyl prep in general?
I've googled my butt off and I've looked through almost every book I've got, almost nothing on silanes. This summer when I give
B-trinitroborazine a shot I need trimethylsilyl nitrate. The reaction will be a variation of a reaction that involves trimethylsilyl azide. I found
a prep for trimethylsilyl azide but its starting material is chlorotrimethylsilane. I've looked all over the place for any mention of
preparation but to no avail. The closest I've come is (CH3)2SiCl2 from heating a copper/silicon alloy in a stream of CH3Cl @ 300C. So, does
anyone have any novel method for producing chlorotrimethylsilane or maybe save me a step and produce trimethylsilyl nitrate in one step?
I'm assuming that everyone here realizes I'm not in search of some OTC method, I think that would be asking a bit much, lol.
[Edited on 3/9/2004 by BromicAcid]
|
|
|
BromicAcid
International Hazard
Posts: 3227
Registered: 13-7-2003
Location: Wisconsin
Member Is Offline
Mood: Rock n' Roll
|
|
Well, it looks like (CH3)3SiCl is quite a hassle to make at home. Oh well, so I decided that I will just buy a bit. So, off to the library I went to
find a synthesis for trimethylsilyl nitrate, I had my ideas but of course there had to be extra complications.
Hours later I found out there weren't. Mix (CH3)3SiCl with AgNO3 and AgCl precipitates out leaving you with the (CH3)3SiNO3 can be done without
a solvent or with CH3CN.
(CH3)3SiNO3 is a very interesting nitrating agent. It gave extraordinarily high yields with aromatics, replacing chlorine's with nitro groups
and just nitrating in general, I'm talking like 96% yields in one shot (BTW I found the reference on how to make the nitrate in Organic Synthesis
Journal so of course it was buried in a massive article on how good a nitrating agent it is). Overall though it is quite the interesing molecule.
However I searched Gmelin and such and the chemical properties page showed nothing of stability. I only wonder because the prep describes how to make
it by the milliliter, almost like more is suicidal.
The azide compound is by contrast incredibly stable. I found a synthesis for that online and it only starts to decompose around 240C and then only
sluggishly. It parallels the nitrate in that it is very good for putting azide groups on pretty much everything.
Finally one of the interesting things is that many of the reactions produce (CH3)3SiCl as the end product, which evaporates off, so, collect, reuse,
and recycle.
|
|
|
The_Davster
A pnictogen
Posts: 2861
Registered: 18-11-2003
Member Is Offline
Mood: .
|
|
Do you still have the site for the azide synthesis?, I would be interested in that.
|
|
|
BromicAcid
International Hazard
Posts: 3227
Registered: 13-7-2003
Location: Wisconsin
Member Is Offline
Mood: Rock n' Roll
|
|
Trimethylsilyl Azide
Also if you're interested in the B-triazoborazine I posted a bit about it in the boron containing molecular explosives thread.
[Edited on 3/17/2004 by BromicAcid]
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
