I already mentioned a sustained current interest in flow chemistry. I am a believer in this method. It is interesting to see reports where chemistry is run in thin capillaries where residence time rules. This parameter is unheard of in our typical “flask-based” reactions. Of particular significance to me is the paper by my former PhD student, Zhi He, who is now doing his postdoctoral work with Tim Jamison at MIT. Zhi’s manuscript, which just came out in Angewandte, documents a flow approach to phenols starting from Grignard reagents. This work serves as an example of an economical approach to phenol synthesis, whereby aryl Grignard reagents are directly oxidized using compressed air in “continuous gas-liquid segmented flow system”. Many functional groups are tolerated in this process. What’s interesting is that the determined reaction profile prescribes the optimal region of pressure/temperature around -25 oC and 200 psi. An opportunity to quickly scan the 2D pressure/temperature grid is powerful. The concept of residence time is critical to the success of flow approaches and, given the importance of kinetics in chemistry, there is potential to look at space/time control of REALLY exotic intermediates.
In vivo, in vitro, in silico… How about in fluo? After all, “fluo” is the Latin for flow. Have you heard anyone refer to flow synthesis this way? I just thought about this term now, but there are probably precedents of its use out there.
Great job, Zhi!