A nanostructured bifunctional acid–base catalyst resin formed by lyotropic liquid crystal monomers

Abstract

An ordered, nanoporous polymer resin was prepared from the self-assembly of lyotropic liquid crystal monomers and employed as a heterogeneous, bifunctional catalyst. This material contains antagonistic acid and base sites in the periodic nanopores and efficiently catalyzes a model tandem reaction (i.e., the deacetalization–nitroaldol reaction between benzaldehyde dimethyl acetal and nitromethane to yield β-nitrostyrene) with excellent product selectivity. This lyotropic liquid crystal-based solid catalyst represents one of the few examples of polymeric tandem catalysts synthesized by a “bottom-up” strategy that imparts control over the stoichiometry of acidic and basic monomers and is the only reported example of a lyotropic liquid crystal-based polymer that contains mutually incompatible catalytic groups. Furthermore, this heterogeneous catalyst is highly active, exhibiting a turnover frequency for this tandem test reaction that exceeds other reported catalytic polymeric materials.