Halogen dance process

Examples exist of rearrangements in which a halogen atom migrates from annular nitrogen to carbon, or from one ring carbon to another ( halogen-dance or transmetalation). Such processes occasionally have preparative importance, and they will be covered in the appropriate sections. 

The halogen dance reaction with base on 2-thiazolamine systems has been reported giving access to 5-substituted 4-bromo-2-thiazolamine derivatives (Scheme 60). The dance reaction is a favoured process and prevention is only possible when optimized reaction conditions and selected electrophiles are applied.95... 

Bakeev, K. A. (Ed.). (2005). Process Analytical Technology - Spectroscopic tools and implementation strategies for the Chemical and Pharmaceutical Industries, Blackwell Publishing Ltd., ISBN 9781405121033, Oxford/UK Bobrovsky, R. Hametner, C. Kalt, W. Froehlich J. (2008). Selective Halogen Dance Reactions at 5,5 -Dibromo-2,2 -bithiophene. Heterocycles Vol.76, No.2, pp. 1249-1259, ISSN 0385-5414... 

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