Green Method for the Synthesis of Chromeno[2,3-c]pyrazol-4(1H)-ones through Ionic Liquid Promoted Directed Annulation of 5-(Aryloxy)-1H-pyrazole-4-carbaldehydes in Aqueous Media
摘要:
The first classical heterocyclic ionic liquid (IL) promoted C-H bond oxidant cross-doupling,reaction for the intramolecular annulation of 5-(aryloxy)-1H-pyrazole-4-carbal- dehydes to chromeno[2,37c]pyrazol-4(1H)-ones has been disclosed The promoter 1,3-dibutyl-1H-benzo[d]fl 2 3]- triazol-34-ium bromide can be easily recycled reused with the same efficacies for at least five cycles in aqueous medium The strategy works smoothly and provides applicable protocol to construct a Wide range of products.