pHarmacist (pHantasticant)
11-20-03 00:50
No 471835
      Direct Nitration of Alkanes     

Electrophilic nitration of alkanes with nitronium hexafluorophosphate
George A. Olah,* Pichika Ramaiah, and G. K. Surya Prakash
Proc. Natl. Acad. Sci. USA. 1997 October 28; 94 (22): 11783–11785 (http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=23573)

Nitration of alkanes such as methane, ethane, propane, n-butane, isobutane, neopentane, and cyclohexane was carried out with nitronium hexafluorophosphate in methylene chloride or nitroethane solution. Nitration of methane, albeit in poor yield, required protolytic activation of the nitronium ion. The results indicate direct electrophilic insertion of NO2 + into CH and CC ó-bonds.

http://www.bassdrive.com/BassDrive.m3u
 
 
 
 
    Rhodium
(Chief Bee)
11-20-03 08:48
No 471908
      nitronium triacontadollar per gram     

nitronium hexafluorophosphate

Ouch - how is this made? It sounds like an awfully expensive reagent - nitronium tetrafluoroborate is €150/25g in the Aldrich catalog and the hexafluorophosphate isn't even listed...

I think gas-phase nitration with HNO3 wins over this method for all purposes except to write a fancy publication.
 
 
 
 
    Antoncho
(Official Hive Translator)
11-20-03 09:39
No 471920
      How it's made:     

Ouch - how is this made?

Not that i'm interested in it, but, - since you asked...smile

It's made by adding PF5 to the mixture of anh. HNO3/HF and filtering the pptated saltlaugh Sounds like fun, doesn't it?smile

HF can bee formed in situ from the same pentafluoride, yield in this case sucks, though - see Patent US3092459

Other perfluoro Lewis acids may bee used as well, see Patent US3403987




Antoncho