A Novel Dewar-Like Reactor for Maintaining Constant Heat and Enhancing Product Yields during Microwave-Assisted Organic Syntheses

摘要

A novel microwave reaction vessel is herein proposed for maintaining constant heat during microwave-assisted organic syntheses. The structure of the vessel is Dewar-like in that it prevents conduction of microwave-generated heat in dielectric substrates into the surroundings. The potential of the double-walled vacuum-filled vessel has been examined for the absence of thermal gradients in aqueous media (homogeneous media) and in the synthesis of biphenyl in a nonpolar solvent (heterogeneous media) involving the Suiuki-Miyaura coupling reaction. The efficiency of the microwave-assisted organic synthesis was enhanced significantly (6- to 7-fold) with this double-walled vessel relative to the conventional single-walled reactor vessel currently used in commercial microwave chemical devices.