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The Hive => Chemistry Discourse => Topic started by: hydroxyindolent on December 23, 2003, 07:48:00 AM

Title: Brominating Power of NBS?
Post by: hydroxyindolent on December 23, 2003, 07:48:00 AM

Greetings!
Can anyone enlighten me as to the synthetic utility of NBS (n-bromosuccinimide)?  Can it brominate a cyclic alkane for instance?  How effective is this reagent compared to elemental bromine?

Title: NBS generates bromine radicals that will ...
Post by: Nicodem on December 23, 2003, 10:58:00 AM

NBS generates bromine radicals that will potentialy substitute any easily abstractable hydrogen. Therefore it is most usefull for the allylic position (alpha to the double bond) and benzylic but sometimes also other positions as well if there is nothing better.
Bromine behaves like an electrophyle (except in special conditions: UV or peroxide) and is therefore useful for elctrophilic substitutions and additions: substitutions of aromatic hydrogens, addition on the double/triple bond...