Sciencemadness Discussion Board

how to get 5-Bromo-2-pyridinecarbonitrile?

millerxia - 15-5-2008 at 16:50

i want to get 5-Bromo-2-pyridinecarbonitrile from 2,5-dibromopyridine and NaCN, but there are too many side reactions.

anyone who can give me some suggestions? or tell me the reaction condition, thanks a lot.:o

ShadowWarrior4444 - 15-5-2008 at 17:01

Making histamine blockers? *curiosity* (Or maybe Hep-C anti-virals!)

I would suggest searching Orgsyn, but I already have by name and CAS number, returning nothing.

The following patents may be of assistance:
2-Pyridinecarbonitrile compounds Neville Finch et al

5-Phenoxy-2-pyridinecarbonitrile compounds and methods for their production Donald E. Butler

TETRAHYDROBENZAZEPINES AS ANTAGONISTS

There was also something clever in the last one about using them to reverse amnesia.

[Edited on 5-15-2008 by ShadowWarrior4444]

Nicodem - 16-5-2008 at 00:33

You should describe the procedure you use now or give a reference for it. You did not even bother telling what side products form, not even what reagent you use. Besides, asking one line questions without showing any effort in searching the literature yourself should be addressed in the Beginnings section where I'm moving this (The Organic chemistry section is for discussions, meaning that you have to open a new thread by properly preparing a topic to discuss). Not mention that it does not even sound much of a question pertaining to amateur chemistry.

Preparations from 2,5-dibromopyridine:

Organometallics, 26 (2007) 5066-5078.
Bioorganic & Medicinal Chemistry, 12 (2004) 5909-5915.
Synthetic Communications, 33 (2003), 3285-3289.
Journal of Medicinal Chemistry, 46 (2003) 4761-4769.

JohnWW - 16-5-2008 at 00:50

Please download those restricted articles and patents, and post them here, someone. Thanks.

Nicodem - 16-5-2008 at 01:07

Patents can not be restricted! The law about patents says they must be public and since the advent of the internet most patents have been scanned and put on public display:
http://ep.espacenet.com/
http://www.wipo.int/patentscope/en
...and many other sites where you can download full patents free of charge.
As for the articles, you have access to References section, so specify which one you need and ask for it. Surely you don't expect every reference given will be accompanied by an attachment with the full paper? That would be an incredible waste of forum bandwidth if so much irrelevant material would be uploaded/downloaded.

F2Chemist - 30-6-2008 at 15:03

If you can afford it (~$75 per 5 grams), start with 2-fluoro-5-bromopyridine...it will be much more selective for the 2 position.

If you already have a boatload of the dibromo, you can always make some of the 2-fluoro with KF-sulfolane, KF-DMSO, TMAF, TBAF, etc. Just remember that your KF and solvent need to be extremely dry otherwise you'll get hydrolysis at the 2 position.