Microwave assisted 1,3-dipolar cycloddition reactions of 2-(4-halobenzoyl) phthalazinium methylides

The cycloaddition reactions, in liquid and solid phase, of 2-(4-halobenzoyl) phthalazinium methylides to activated alkenes and alkynes by classical heating and under microwaves were studied. The microwave assisted reaction of phthalazinium ylides to activated alkenes and alkynes shows a remarkable acceleration under microwave irradiation and allows the general and facile synthesis. 2-(4-halobenzoyl) phthalazinium methylides show a different behaviour of reactivity in liquid and solid phases and a possible explanation is furnished. A comparative study, microwave-classical heating on the one hand and reactions in liquid and solid phases on the other has been done.