A homochiral metal-organic porous material for enantioselective separationand catalysis

Inorganic zeolites are used for many practical applications that exploit th e microporosity intrinsic to their crystal structures. Organic analogues, w hich are assembled from modular organic building blocks linked through non- covalent interactions, are of interest for similar applications. These rang e from catalysis, separation and sensor technology to optoelectronics(1-3), with enantioselective separation and catalysis being especially important for the chemical and pharmaceutical industries. The modular construction of these analogues allows flexible and rational design, as both the architect ure and chemical functionality of the micropores can, in principle, be prec isely controlled. Porous organic solids with large voids and high framework stability have been produced(14,15), and investigations into the range of accessible pore functionalities have been initiated(7,11,12,16-23). For exa mple, catalytically active organic zeolite analogues are known(13,22,23), a s are chiral metal-organic open-framework materials. However, the latter ar e only available as racemic mixtures(24,25), or lack the degree of framewor k stability or void space that is required for practical applications(26,27 ). Here we report the synthesis of a homochiral metal-organic porous materi al that allows the enantioselective inclusion of metal complexes in its por es and catalyses a transesterification reaction in an enantioselective mann er. Our synthesis strategy, which uses enantiopure metal-organic clusters a s secondary building blocks(14), should be readily applicable to chemically modified cluster components and thus provide access to a wide range of por ous organic materials suitable for enantioselective separation and catalysi s.