An Efficient, Ligand-Free, Heterogeneous Supported Copper Hydroxide Catalyst for the Synthesis of N,N-Bicyclic Pyrazolidinone Derivatives

摘要

Truly heterogeneous with retention of its high performance: The 1,3-dipolar cycloaddition of azomethine imines to terminal alkynes was efficiently promoted by the easily prepared, inexpensive, supported copper hydroxide, Cu(OH)_x/Al₂O₃. Various kinds of azomethine imines and terminal alkynes could be utilized as dipoles and dipolarophiles, respectively, to form the corresponding N,N-bicyclic pyrazolidinone derivatives in high yields.