An unusual example of a 1,1-cycloaddition reaction of a diazoalkane

Article abstract of DOI:10.1016/S0040-4039(00)78825-3

Thermolysis of the sodium salt of E-1,4-diphenyl-3-buten-1-one N-tosylhydrazone gave rise to the corresponding diazoalkane which undergoes a subsequent 1,1-cycloaddition reaction to produce 3,6-diphenyl-1,2-diazabicyclo[3.1.0]hex-2-ene.