Reaction of diazoalkanes with unsaturated compounds - 13. A new method of preparation and [1+2]- and [3+2]-cycloaddition reactions of diazopropyne

A THF solution of diazopropyne was obtained in 60% yield by the reaction of a 30% aqueous solution of methylamine with N,N'-dinitroso-N,N'-dipropargyl terephthalodiamide. The reactions of diazopropyne with methyl acrylate and methyl methacrylate giving various ethynylpyrazolines as well as its CuCl-c atalyzed decomposition in the presence of norbornene or norbornadiene yield ing ethynylcyclopropanes were studied. The main products of catalytic deazo tization of diazopropyne in the absence of unsaturated compounds are isomer ic E- and Z-hex-3-ene-1,5-diynes resulting from propargylene dimerization.