againa - 28-4-2005 at 17:48
PV=nRT just isn’t working right now.
Any thoughts are appreciated.
A friend wants to decarboxylate an amino acid in a technoish way and has some questions.
From friend’s O chem text book, one would get the impression that this reaction simply requires heat. Research (the reading kind) has shown that
it’s not necessarily so simple. The thing that seems to look best from friend’s findings is a boil in high boiling solvent (cyclohexanol) with an
enone cat. Well that’s great, but he wants to get techno.
So…..has a Teflon digestion vessel round the lab, the small kind with a 75 psi rating.
So….. throw in some solvent and see what happens? Solvent boils higher temp thanks to microwave, solvent boils higher pressure (closed digestion
vessel) if decarboxlation works (friend thinks that Le Chateleir’s P. would not simply reattach CO2 to amine) then even more pressure, more
pressure, higher temp…..don’t want a Teflon solvent grenade going of in the microwave.
So this situation quickly goes past friend’s gas law knowledge confidence.
How does this microwave bomb madness work? If friend wants to give it a go what makes the most sense: lots of solvent (little head space) and small
amount of amino acid? How bout, not a lot of solvent and more amino? Is friend’s thoughts concerning different phases and Le Chateleir’s principle
true, or would any freed CO2 simply reattach and equalibriam established in the closed vessel.
Any thoughts, really, on this subject would be very welcomed.
Thanks!
Re: Microwave Assisted Chemistry
solo - 29-4-2005 at 08:30
Here is a wealth of information on microwave assisted chemistry..........solo
http://www.milestonesrl.com/analytical/resources/media.html
Magpie - 29-4-2005 at 09:00
I would defintely recommend preliminary experiments on a small scale with a limited amount of reactant and solvent.
Does your friend's bomb have a pressure relief valve, rupture disk, or a port to attach a pressure guage. With a guage your friend could monitor
the reaction progress and hit the kill switch if the pressure gets too high.
What pressure does your friend need to attain and how will he vent the CO2?