1,3-DIPOLAR CYCLOADDITION REACTIONS OF SOME 3-ARYL-PHTHALAZINIUM-1-OLATES

The participation of halogen substituted 3-aryl-phthalazinium-1-olates in cycloaddition reactions were stud ed with various olefinic and ace tylenic dipolarophiles. The betaines gave the expected cycloadducts wi th vinyl acetate, vinyl phenyl ether, and vinyl phenyl sulfide. Howeve r, two isomeric products were obtained with diethyl acetylenedicarboxy late. One of them was the normal expected cycloadduct and the other on e was the rearranged cycloadduct. On the other hand, reactions with ph enyl acetylene produced only the rearranged cycloadducts.