The amino induced elimination of benzisoxazole into the relevant o-cyanophenolate ion (Kemp elimination)has been studied in [bmim][BF4] solution at 298 K. To have information about the interactions betweenreactants and ionic liquid, the reaction has been carried out at different temperatures (293–313 K). Severalprimary, secondary, and tertiary amines have been used to study the effect of amine structure on thereaction rate. The collected data show that the amine structure seems to have a crucial role in determiningthe reaction rate. Furthermore, as different cation or anion structures of an ionic liquid can significantlyaffect its properties, the title reaction has been performed in four different ionic liquids ([bmim][PF6],[bmim][NTf2], [bm2im][NTf2], and [bmpyrr][NTf2]), using pyrrolidine and piperidine as model amines.An H-donor negative solvent (MeOH and [bmim][NTf2]) effect on reaction rate was detected. Finally, anarrow range of activation parameters was calculated both for the reaction induced by different aminesand for pyrrolidine and piperidine, in the presence of different ILs. This fact suggests the occurrence ofan “early” transition state.
|Number of pages||7|
|Journal||Journal of Organic Chemistry|
|Publication status||Published - 2008|
All Science Journal Classification (ASJC) codes
- Organic Chemistry