Functionalised Pyrazoles through a Facile One-Pot Procedure from N-Tosyl-N-propargyl-hydrazine and Aryl Iodides or Vinyl Triflates
31. Dezember 2000 (online)
Functionalised pyrazoles have been prepared in good overall yield through a facile one-pot procedure. The synthesis includes the palladium-catalysed coupling of the readily available N-tosyl-N-propargylhydrazine with aryl iodides or vinyl triflates, the palladium-catalysed annulation of the resulting N-tosyl-N-(1-aryl/vinyl-1-propyn-3-yl)hydrazine and exposure of the reaction mixture arising from the annulation step to KOBut.
pyrazoles - palladium catalysis - coupling - annulation - aryl iodides - vinyl triflates