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Updated: Mar 21, 2026
Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
Published on: December 16, 2019
Scalable anti-Markovnikov hydrobromination of aliphatic and aromatic olefins
Marzia Galli1, Catherine J Fletcher, Marc Del Pozo
1Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK. s.goldup@soton.ac.uk.
Abstract:
To improve access to a key synthetic intermediate we targeted a direct hydrobromination-Negishi route. Unsurprisingly, the anti-Markovnikov addition of HBr to estragole in the presence of AIBN proved successful. However, even in the absence of an added initiator, anti-Markovnikov addition was observed. Re-examination of early reports revealed that selective Markovnikov addition, often simply termed "normal" addition, is not always observed with HBr unless air is excluded, leading to the rediscovery of a reproducible and scalable initiator-free protocol.
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