Microwave-assisted asymmetric organocatalysis: A probe for nonthermal microwave effects and the concept of simultaneous cooling

A series of five known symmetric organocatalytic reactions at elevated temperatures are re-evaluated to detect the existence of specific or nonthermal microwave effects. The results obtained either with microwave irradiation or with microwave irradiation with simultaneous cooling might be reproduced by conventional heating at the same reaction temperature and time in an oil bath, though no evidence was found for specific or nonthermal effects.