Real-Time in situ Raman Analysis of Microwave-Assisted Organic Reactions

Integration of a Raman probe into a commercially available microwave synthesizer has demonstrated unprecedented utility in understanding chemical processes within the rapidly emerging field of microwave-assisted organic synthesis. The real-time spectral feedback afforded by this system has facilitated analysis of reaction mechanisms, reactive intermediates, and reaction kinetics via optical sampling through the sidewall of the sealed reaction vial within the microwave chamber. The feasibility, attributes, and limitations of the system are illustrated using amine coupling and Knoevenagel coupling example reactions. In addition to the reported analyses, this system provided the safety of remote sensing, adequate sensitivity, ease of alignment, and optimized “depth of field” for analysis of solutions with solids content.