Comparative Study Using Different Infrared Zones of the Solventless Activation of Organic Reactions

Abstract

In this work, the results of a study comparing the use of irradiation from different regions of the infrared spectrum for the promotion of several organic reactions, are presented and discussed. This use of eco-conditions provides a green approach to chemical synthesis. A set of ten different organic reactions were evaluated, including the Knoevenagel, Hantzsch, Biginelli and Meldrum reactions. It is important to highlight the use of a commercial device that produces infrared irradiation in the near infrared region and its distribution by convection providing heating uniformity, significantly reducing reaction times, achieving good yields and proceeding in the absence of solvent. It is also worth noting that a variety of different reactions may be performed at the same time. Finally, the products obtained were identified using TLC, together with corresponding MS-data, complementarily in comparison of NMR 1H and 13C data with literature information.

The intracellular interaction of biomolecules by means of emission and resonance of infrared photons. A hypothesis.

“…With the help of sufficient energy of specific wavelengths, many chemical reactions can be carried out e.g. by means of lasers (59,60).…”

The Possible Role of Molecular Vibration in Intracellular Signalling

“…With the help of specific EM radiation und sufficient radiation energy, numerous chemical reactions can be triggered or carried out, which is used in technical processes [43,44]. In the hypothesis presented here, however, the central aspect is not the transfer of energy but the recognition and transmission of information employing EM frequency patterns.…”

Synthesis of Cycloveratrylene Macrocycles and Benzyl Oligomers Catalysed by Bentonite under Microwave/Infrared and Solvent-Free Conditions

“…Microwave reactions were performed in a CEM Discover LabMate instrument. The middle infrared irradiation was performed using a Phillips IR lamp (375 W/220 V) integrated to an infrared reactor designed by our research group [46,47,48], and validated by a wide number of applications.…”

“…Presently, we desire to extend that knowledge to the development of a process that is more efficient, eliminates the use of solvent and halogenated starting materials, reduces reaction times and avoids tedious workup protocols. With these ideas in mind, we synthesised cycloveratrylene macrocycles and benzyl oligomers from the combination of Tonsil Actisil FF (TAFF), a commercial bentonite clay previously characterized by our group [5,6], with microwave-assisted organic synthesis (MAOS) [41,42,43,4445] or infrared irradiation [46,47,48,49,50,51,52] in the absence of a solvent. In addition, computational chemistry calculations were performed to establish a validated mechanistic pathway to explain the growth of the obtained linear oligomers.…”