Acid catalyzed synthesis of carbonyl-functionalized microporous ladder polymers with high surface area

The synthesis of a new class of very rigid, microporous ladder polymers in a cyclotrimerization reaction of bifunctional diketo-s-indacene-type monomers is described. The cyclotrimerization reaction is carried out under Lewis-acidic (TiCl4) or, preferentially, acidic conditions (methanesulfonic acid—MSA) and yields ladder-type, aromatic networks with high BET surface areas of up to 1650 m2 g−1. The synthetic scheme towards the truxene-cored ladder networks also allows for the incorporation of carbonyl functions that may be transformed to other functionalities in further derivatization reactions.