488
Safaei-Ghomi et al.
evaporated under reduced pressure and the product was recrystallyzed from ethanol. The
23
spectral data of all products were identical to those reported in a previous paper.
Typical Procedure for the Preparation of Indazole Derivatives (5a–p) in [bmim]Br
A mixture of 3a-h (1 mmol) and [bmim]Br (153 mg, 0.7 mmol) was added to hydrazine
◦
hydrate or phenylhydrazine (1.5 mmol). The mixture was refluxed for 3.5 h at 90 C. The
reaction mixture was extracted with ether (3×10 mL) and the ionic liquid phase was
separated. The residual ionic liquid may be reused in the next run if necessary after a 2 h
heat treatment under vacuum. The ethereal layer was evaporated under reduced pressure
and the product was recrystallyzed from ethanol. The spectral data of all products were
25
identical to those reported in a previous paper.
Acknowledgements
Financial support from the Research Affairs Office of the University of Kashan, Kashan, I.
R. Iran is gratefully acknowledged.
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