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Two chiral porous Fe(salen)-based metal-organic frameworks are constructed and are shown to be efficient and recyclable heterogeneous catalysts for asymmetric oxidation of sulfides to sulfoxides with an enantioselectivity of up to 96%.

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An important challenge in asymmetric cascade reactions is solving the intrinsic incompatibility of two types of distinct organometallic complexes that participate in a one‐pot reaction. Herein, we develop an organoruthenium‐/organopalladium‐bifunctionalized periodic mesoporous organosilica and realize one‐pot cascade reactions of Ru‐catalyzed asymmetric transfer hydrogenation and Pd‐relay‐catalyzed cross‐coupling of haloacetophenones and arylboronic acids to various chiral biaryl alcohols, with quantitative conversions and up to 98 % enantioselectivity in an aqueous medium. This characteristics is attributed to the site‐isolated, uniformly distributed, well‐defined single‐site palladium and ruthenium active species. Furthermore, the heterogeneous catalyst is conveniently recovered and reused repeatedly for eight times without loss of its catalytic activity, showing particular attractiveness for practicing organic transformation.

Chiral cinchona-based squaramide-functionalized organic−inorganic hybrid silica is developed through postgrafting 3-mercaptopropyltrimethoxylsilane onto imidazolium-based organic−inorganic hybrid silica, followed by the anchor of a squaramide organocatalyst via a thiolene click method. Structural characterizations and spectroscopic analyses demonstrate that a well-defined single-site chiral cinchona-based squaramide active center is incorporated onto the organic−inorganic hybrid silica. As a bifunctional heterogeneous catalyst, it displays excellent catalytic activity and high enantioselectivity in asymmetric Michael addition of 1,3-dicarbonyl compounds to nitroalkenes in brine. As presented in this study, the synergistic effect of confined site-isolated squaramide species and a salient imidazolium phase-transfer function significantly accelerates the catalytic performance. Furthermore, the organic−inorganic hybrid silica is conveniently recovered and reused at least eight times without loss of catalytic activity, showing an attractive feature in practice of organic transformation in an environmentally friendly manner.