Synthesis of 4-aryl-5,5-dimethyl-5H-l,2,3-triazoles and 4-aryl-3-cyano-5,5-dimethyl A~1-pyrazolines by cycloaddition of 2-diazopropane with iminoethers and propenenitriles

摘要

A regiospecific 1,3-dipolar cycloaddition of 2-diazopropane 3 to iminoethers la-c,carried out at 0 deg C,afforded in two steps the corresponding 4-aryl-5,5-dimethyl-5H-l,2,3-triazoles 5a-c.Under the same conditions,3-arylpropenenitriles 2a-d led to 3-cyano-5,5-dimethyl DELTA~1-pyrazoLines 6a-d.Products 4-6 were obtained in good yields (69-85%).