1,3-dipolar cycloaddition of in situ generated 2,2-dimethyl- and 2,2-dichlorodiazocyclopropanes to 3,3-dimethylcyclopropene

Article abstract of DOI:10.1007/BF01431115

2,2-Dimethyl- and 2,2-dichlorocyclopropyl-N-nitrosoureas were synthesized for the first time. Under the action of MeONa/MeOH at -10°C, these compounds generate the corresponding 2,2-dimethyl- and 2,2-dichlorodiazocyclopropanes, which are readily trapped by 3,3-dimethylcyclopropene to give the products of 1,3-dipolar cycloaddition, viz., isomeric substituted spiro{2,3-diazabicyclo[3.1.0]hex-2-ene-4,1′-cyclopropanes}, in yields of about 70%.