Author Topic: Applications of NBS?  (Read 1559 times)

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psyx7

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Applications of NBS?
« on: January 07, 2004, 06:52:00 AM »
I know that N-BS can bee used to brominate substituted benzenes, and apparently also amines. But there a couple of questions that I have been unable to find answers to despite using both TFSE and Google:

Can NBS be used to selectively brominate aldehydes and ketones, e.g. 2,5-DMP2P __> 4-Br-2,5-DMP2P or 2,5-DMB __> 4-Br-2,5-DMB?

I have a feeling that the answer is probably no since I have been unable to find any references to it, but thought I'd check with the experts first  ;D

TIA,
psyx

hest

  • Guest
NBS
« Reply #1 on: January 07, 2004, 10:12:00 AM »
Bromination of the aromatic core with NBS in the dark works greath, use DCM or Acetonitrile as solvent, red this [ url ]

https://www.thevespiary.org/rhodium/Rhodium/chemistry/2cbde.html

[ /url ]

Nicodem

  • Guest
I don't think it would work for 2,5-DMP2P...
« Reply #2 on: January 07, 2004, 11:45:00 AM »
I don't think it would work for
2,5-DMP2P -> 4-Br-2,5-DMP2P
because of the ketone group.
Even though NBS does not produce Br2 it does produce free radicals and slowly also some electrophilic Br+ (in dark) and these react readily with the alpha-hydrogens of ketones like 2,5-DMP2P (producing some just some useless 'tear-gas' compounds).