Cu+‐catalyzed 1,3‐Dipolar Intramolecular Click Opposite Cross Cyclization Reaction of Polyoxyethylene Bis(azido‐terminal alkynes): Synthesis of New 1,2,3‐Triazolo‐crown Ethers

The Cu⁺ catalyzed, 1,3‐dipolar cycloaddition of polyoxyethylene di(azidoalkynes), yields a mixture of the polyoxyethylene 1,5‐disubstituted fused di(1,2,3‐triazole‐1,4‐oxazines) as the major product, and the 1,4‐disubstituted mono‐(1,2,3‐triazolo) azidoalkyne crown ether.