Metal-organic porous materials are receiving growing attention [1] because of their potential applications in gas storage, [2] separation, [3] and many other areas. [4] Although catalysis is one of the most promising applications of such materials, only a handful of examples have been reported to date. [5] Furthermore, despite considerable efforts, attempts to synthesize robust, homochiral metal-organic porous materials capable of enantioselective separation and/or catalysis have met with only limited success. [6,7] Most homochiral metalorganic frameworks are not robust enough to show permanent porosity, nor porous enough to be useful for selective sorption or catalytic transformation of organic molecules. Therefore, the synthesis of robust homochiral metal-organic frameworks with potential for application is still challenging. For the synthesis of homochiral metal-organic open frameworks, two general approaches have been taken: 1) use of a rigid homochiral organic ligand as a spacer to link adjacent metal centers or secondary building units (SBUs), [5b-d, 7] and 2) use of a homochiral ligand as an auxiliary pendant which does not directly participate in the formation of a framework backbone, but forces the framework to adopt a specific chiral topology.[3d] Herein, we introduce another rational approach to the synthesis of homochiral metal-organic frameworks. A metal ion and a readily available homochiral organic ligand are used to form homochiral SBUs, which in turn, are linked together by rigid spacers to build a network structure, in a one-pot reaction (Scheme 1).[8] With a judicious choice of metal ion, homochiral organic molecule, and rigid polytopic linker (that is, a connector with more than one metal coordination site), this approach allows us to synthesize metal-organic open frameworks with stable chiral pores. Herein, we report a new homochiral metal-organic material that has permanent porosity, size-and enantioselective sorption properties, and catalytic activity.[9]

Chiral bipyrrolidine based iron and manganese complexes [((S,S)-pdp)MII(OTf)2] catalyze the asymmetric epoxidation of various olefins with H2O2 in the presence of carboxylic acid additives with high efficiency (up to 1000 turnover number (TON)) and selectivity (up to 100%), and with good to high enantioselectivity (up to 93% enantiomeric excess (ee)). The enantioselectivity increases with growing steric demand of the acid. On the basis of the electron paramagnetic resonance (EPR) spectroscopy and enantioselectivity studies, the active oxygen-transferring species of the above systems can be identified as structurally similar oxometal(V) species of the type [((S,S)-pdp)MVO(OCOR)]2+ (M = Fe, Mn; R = alkyl).

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(R)- and (S)- enantiomers of alkyl aryl sulfoxides can be obtained by chromatographic resolution of the racemic mixtures of the sulfoxides on a microporous homochiral Zn-organic polymer or by simultaneous catalytic oxidation of the corresponding sulfides with H2O2 and enantioselective chromatographic resolution of the resulting sulfoxides in a one-pot process.