Sciencemadness Discussion Board

Urea microwave organic reaction

mick - 30-9-2005 at 13:27

I am not up to speed on the chemisty of urea but in general it has been used to form heteorcyclic compounds with a bit of heat (160 +) .
I have tried a reaction on Al heating block and it seems to be a mess.
I have seen a ref where microwave assisted reactions with urea are reported to work.
There is an old microwave oven in the lab where I work and I am thinking about trying it.
I was thinking of putting the small scale reaction inside a polypropylene container and microwave it.

mick

Any safety advice with using the microwave oven would be good
mick

[Edited on 30-9-2005 by mick]

I have finally submitted my PhD Thesis to day the age of 50. I am having a beer.
mick

[Edited on 30-9-2005 by mick]

chemoleo - 30-9-2005 at 19:12

Well congratulations to your submission. I hope to do the same in the near future. :)

Nonetheless - would you like to tell us WHAT reaction you are trying to do exactly?
Urea and WHAT?

mick - 1-10-2005 at 08:10

I have tried to copy and paste the reaction but I can not.
The reaction is a 1 amino 2 nitrile heterocyclic with urea which might give an iso-G structure.
mick

mick - 2-10-2005 at 03:43

Attached is the reaction. The literature gives 180 oC for 2 h. I tried 160 oC first for my stuff and nothing happened at 180 oC the urea seemed to decompose ie solidified above its mp and I could not extract anything that looked like product (should fluoresce under UV). I have seen a ref where the yield from a reaction with urea involving ring opening and ring closing was increased from 40% to 80% by using microwaves rather than heat. It looks like a reaction that should work. Urea is acidic but maybe a strong base would get it to add to the nitrile and then it should cyclise.
mick

Firefox crashed at home yesterday and today Firefox crashed on my computer at work?

Chemeleo hope it goes well

Attachment: iso G.doc (19kB)
This file has been downloaded 556 times