(18a) Continuous Fine Chemicals Processing With Aqueous Phase Organic Synthesis
The use of water as a reaction solvent has the potential to impact the sustainable, continuous flow manufacturing of specialty chemicals. Successfully engineering such a process, however, requires the ability to overcome considerable challenges including the discovery of the underlying physical and the chemical rate processes that govern chemical kinetics. The virtually unlimited synthetic opportunities for using unactivated C-H bonds, activated with organometallic catalysts such as palladium and hydrophilic ligands, fosters the inception of aqueous phase organic synthesis at both the laboratory and the production scales. Direct functionalization of C–H bonds has been an aspirational goal throughout the development of modern synthetic organic chemistry. Catalyst recovery and its reuse are potential benefits of aqueous phase cross-coupling reactions, yet liquid-liquid reactions introduce the potential for mass transfer resistances. Choosing the appropriate reactors to study the direct arylation of alkynes requires the application of one’s classical reaction engineering toolbox. In the present work, we examine the palladium-catalyzed synthesis of biaryl fluorinated alkyne using hydrophilic ligand with the goal of evaluating the differences between batch and continuous micro-scale flow reactors.