A one-pot three-step synthesis of Z-trisubstituted olefins from arylalkynes and their cyclization into 4-aryl-2H-chromenes
Rapid and versatile access to (Z)-trisubstituted olefins 2 and their cyclization into 4-aryl-2H-chromenes 1 starting fromarylalkynes 3 is described. In a one-pot fashion, alkynes 3 were first hydrated, then transformed into N-tosylhydrazones, and finally
Palladium-catalyzed coupling of N-tosylhydrazones with ortho substituted aryl halides: Synthesis of 4-arylchromenes and related heterocycles
A convenient and efficient procedure for the synthesis of 4-arylchromenes, thiochromenes, and related heterocycles via a four step-sequence has been developed. The first three steps, which involve hydration of alkynes, hydrazones formation, and their Pd-c