The ring-closing metathesis (RCM) of diethyl diallylmalonate in glycerol micellar conditions was studied using microwave irradiation. The micellization of different cationic surfactants in glycerol was first investigated. The results show the superiority of micellar catalysis in glycerol for a RCM reaction compared to glycerol alone, limiting byproduct formation. In comparison with the classical solution syntheses, the method here described allows safer reaction conditions, less hazardous chemical syntheses, and use of renewable feedstocks. The practical workup, separation, and purification operations minimize the use of materials.

A new hybrid microwave (MW) and ultrasound (US)-assisted reactor concept was investigated. The 2.45 GHz microwaves were delivered with a semiconductor generator via a coaxial cable to a monomode Transverse Electric (TE) microwave resonant cavity within which the reactor was placed; the US (25 kHz) were delivered at the bottom of the TE cavity via a novel designed sonotrode consisting of a detacheable metallic plate-probe (indirect sonication). The semiconductor microwave generator helped to optimize the absorbed energy via its automatic frequency tuning function. The dual MW/US device allowed the use of both technologies separately or in a simultaneous combined manner. The ring-closing metathesis of diethyl diallyl malonate in glycerol micellar conditions was studied as an example using this novel hydrid technology. The results were compared with those obtained when microwaves or ultrasound were applied individually. Various benzylidene-, indenilydene-and Hoveyda-Grubbs-type catalysts were screened. The novel reactor for combined MW/US irradiation showed beneficial effects on the outcome of the reaction."Microwave-Ultrasound Simultaneous Irradiation: a Hybrid Technology applied to Ring Closing Metathesis" Glycerol Micelles were suitable nanoreactors for Ring-Closing Metathesis reaction activated by a hybrid Microwave-Ultrasound reactor. Nine different Ru-catalysts were investigated.