Flow synthesis of coumalic acid and its derivatization

Coumalic acid is a valuable platform compound which can be prepared from malic acid, a biorenewable feedstock readily derived from the fermentation of glucose. Current batch procedures to synthesise coumalic acid have several drawbacks, which we address with the aid of tubular flow systems and a simple heated rotating flow reactor. The prepared coumalate derivatives can be further used in inverse electron demand Diels-Alder reactions to synthesise compounds with many applications including molecular electronics, with the added advantage of providing metal-free preparations.