Special issue in flow chemistry

Abstract

In the last decade, we havewitnessed a steady transformation of organic chemistry. The number of launched new chemical entities decreased in spite of the number of synthetically accessible small molecules that exponentially increased. On the other hand, the drug like chemical space was only poorly sampled and the huge compound decks at Big Pharma companies were saturated with redundant structures. As a consequence, new synthetic techniqueswere required and emerged which were collectively called “enabling chemistry” [1]. Enabling chemistry methods contribute to accelerate chemical processes, explore new chemistries, increase the throughput and facilitate the workup and isolation. Such processes also meet several criteria of Green chemistry (i.e., increased reaction rate, reducing waste, and increased atom economy) and contribute to the development of sustainablemanufacturing (i.e., recycling, biomass transformation, etc.). Enabling chemistry led the way to continuous flow chemistry and microreactors [2]. While the significant advancement in immobilized catalysts and supported reagents naturally found application in continuous flow systems (i.e., fixedbed microreactors) the wide-spread application of microwave-assisted organic synthesis (MAOS) promoted the further expansion of the boundaries of the chemical parameter space [3]. However, the batch nature of synthetic organic chemistry and the chemical parameter space it covers has not changed during the ca. 200 years’ history of organic synthesis and only a small fraction of the parameter space is covered