Preparation of α-Bromoketones and Thiazoles from Ketones with NBS and Thioamides in Ionic Liquids
Yuhta Izumisawa, Hideo Togo
DOI: 10.4236/gsc.2011.13010   PDF    HTML     10,542 Downloads   24,575 Views   Citations


Ketones smoothly reacted with NBS in the presence of a catalytic amount of ptoluenesulfonic acid to give α-bromoketones in good yields in typical ionic liquids, such as [bmim]PF6 and [bmpy]Tf2N, and the ionic liquids could be repeatedly used for the same reaction after the extraction of the α-bromoketones. Then, the one-pot conversion of ketones into thiazoles by the treatment with NBS, and subsequently with thioamides could be also carried out in [bmim]PF6 and [bmpy]Tf2N, respectively Thus, [bmim]PF6 and [bmpy]Tf2N could be used as recyclable reaction media for the preparation α-bromoketones and thiazoles from ketones.

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Y. Izumisawa and H. Togo, "Preparation of α-Bromoketones and Thiazoles from Ketones with NBS and Thioamides in Ionic Liquids," Green and Sustainable Chemistry, Vol. 1 No. 3, 2011, pp. 54-62. doi: 10.4236/gsc.2011.13010.

Conflicts of Interest

The authors declare no conflicts of interest.


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