From: C. Oliver Kappe (oliver.kappe$##$uni-graz.at)
Date: Mon Aug 12 2002 - 03:32:00 EDT
Hi!
The address of the people in Jena, Germany, is:
http://www.ituc.uni-jena.de/
Regards, Oliver
Darren Rhodes schrieb:
>
> A couple of UK companies (Production Techniques Ltd, 13 Kings Road, Fleet,
> Hampshire, Enlgand GU13 9AU tel 01252 616757 facs 01252 615818 and Cowie
> Technology tel 01642 599190 facs 01642 596810) should be able to supply you
> with suitable PTFE vessels.
>
> Does anyone know the name and contact number of the people in Jenna
> (Germany) who are currently using lab scale microwave reactors????
>
> Darren.
>
> ----- Original Message -----
> From: "Jacob Zabicky" <zabicky$##$bgumail.bgu.ac.il>
> To: "Darren Rhodes" <drhodes$##$globalnet.co.uk>;
> <suzukicar$##$belais.freesurf.fr>; <everybody$##$orglist.net>; "Jacob Zabicky"
> <zabicky$##$bgumail.bgu.ac.il>
> Sent: Sunday, August 11, 2002 6:51 AM
> Subject: Re: ORGLIST:Bromination
>
> > Hello again,
> >
> > If we come to microwave reactors, as Darren suggested, ultrasound is also
> > a possibility. IMO in both cases you will need a specially designed
> vessel,
> > both to allow inflow of energy to the reaction mixture and to avoid
> outflow
> > if the deletereous bromine vapors.
> >
> > All the best,
> >
> > Jacob
> >
> > At 13:15 8/8/2, Darren Rhodes wrote:
> > >It would be interesting to this sort of thing under microwave conditions
> ...
> > >This should bring down your reaction time and if you wanted to do the
> work
> > >on a larger scale you could use a continuous flow microwave reactor ...
> For
> > >the batch microwave work talk to http://www.personalchemistry.com/ (the
> web
> > >page seems a bit bloated but it should give you contact details). For
> the
> > >continuous flow ... maybe the personalchemistry people again ??? Perhaps
> > >someone else on the list could give appropriate details and refs and
> perhaps
> > >their own experiences of these techniques .....
> > >
> > >Darren.
> > >
> > >----- Original Message -----
> > >From: "Jacob Zabicky" <zabicky$##$bgumail.bgu.ac.il>
> > >To: <suzukicar$##$belais.freesurf.fr>; <everybody$##$orglist.net>
> > >Sent: Thursday, August 08, 2002 12:32 PM
> > >Subject: Re: ORGLIST:Bromination
> > >
> > >
> > >Hello Bel,
> > >
> > >The pressure in the vessel will be somewhat lower than 4 bar. If your
> > >reaction mixture is over a couple of mL, you should carry out the process
> > >in a Teflon-lined pressure vessel. If you can do it in small batches,
> > >then you can prepare thick-walled test tubes, of outer diameter not
> bigger
> > >than say 10 mm, place your mixture, freeze it with ice-salt or other
> > >cooling medium (below -10C), and seal the tubes while slightly evacuating
> > >at the end.
> > >
> > >You can place the tubes in boiling water or in a temperature-controlled
> > >heating block, all this, of course in a well protected hood. Thick-walled
> > >tubes of small diameter withold some pressure quite well.
> > >
> > >Good luck,
> > >
> > >Jacob
> > >
> > >
> > >At 16:23 7/8/2, Bel wrote:
> > >>Dear all,
> > >>
> > >>I would like to know If any has experience with bromination in harsh
> > >>conditions, using sealed tube at high temperature. I found one procedure
> > >>concerning the bromination of an electronically poor aromatic
> (pyridinium
> > >>derivative) which must be done by heating during 3 days at 180C. The
> > >>bromine's boiling point is 58.7C, which means a very high pressure in
> the
> > >>tube at 180C. So does anyone know how to make such reaction in a safe
> way,
> > >>and which kind of tube may resist to such pressure?
> > >>
> > >>Regards
> > >>
> > >>Bel
-- C. Oliver Kappe Institute of Chemistry Karl-Franzens-University Graz Phone: +43-316-3805352 Heinrichstrasse 28, A-8010 Graz Fax: +43-316-3809840 AUSTRIA e-mail: oliver.kappe$##$uni-graz.at http://www-ang.kfunigraz.ac.at/~kappeco _______________________________________________ ORGLIST - Organic Chemistry Mailing List Website / Archive / FAQ: http://www.orglist.net To post a message (TO EVERYBODY) send to everybody$##$orglist.net To unsubscribe, send to everybody-request$##$orglist.net the message: unsubscribe your_orglist_password your_address List coordinator: Joao Aires de Sousa (coordinator$##$orglist.net)
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