Concerning the Absence of Microwave Effects

Concerning the Absence of Microwave Effects 209 4.8.4.6 Rearrangement of Ammonium Ylides... 

In conclusion, Kappe s group demonstrated the absence of any differences between conventional and microwave heating in proline-catalyzed Mannich and aldol reactions as well as no evidence for specific or non-thermal microwave effects. In all cases, in contrast to the previous literature reports, the results obtained with microwave irradiation could be reproduced by conventional heating at the same reaction temperature and time in an oil bath. The differences observed in previous publications could be a result of incorrect temperature measurements [36]. After Kappe s [35] publication several articles appeared in the literature concerning the application of microwaves in asymmetric organocatalysis, mostly in aldol and Michael type reactions operating via enamine as well as iminium catalysis. 

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