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An asymmetric transfer hydrogenation of 2‐oxazolones in the presence of a chiral diamine ruthenium catalyst with potassium formate as a hydrogen source and potassium carbonate as an additive in 2,2,2‐trifluoroethanol is described. A series of chiral 2‐oxazolidinones were obtained with 29%–95% yields and 86%–>99% ee's. Furthermore, gram‐scale synthesis of chiral 2‐oxazolidinone and its downstream derivatizations demonstrate the practicality of this method. [ABSTRACT FROM AUTHOR]

Polyamide reverse osmosis membranes are indispensable for the worldwide clean water supply. Incorporation of nanomaterials into polyamide separation layer provides an evident methodology to enhance the water flux. However, the desalination performance would be compromised by the inadequate compatibility between the nanomaterial and the polyamide matrix. In this work, we propose a straightforward strategy to use covalent organic frameworks (COF) nanofibers as the efficient nanofiller for the fabrication of high flux polyamide membranes. The COF nanofibers featuring crystalline structures, large surface area and well‐defined micropores are synthesized by a surfactant‐mediated solvothermal method. It is found that the COF nanofibers are able to mediate the interfacial polymerization process via the controlled release of amine molecules. This creates the reduced thickness of the polyamide separation layer. Moreover, the rigid and permanent nanopores of COF could serve as additional channels for water permeation. Benefitting from the low thickness and the additional channels, thus fabricated membranes exhibit a significantly enhanced water flux, while maintaining a slightly improved NaCl rejection. Our work is expected to provide a new insight for the design and fabrication of advanced polyamide reverse osmosis membranes. [ABSTRACT FROM AUTHOR]

Organic solvent nanofiltration (OSN) has become increasingly important in petrochemical and pharmaceutical industries, demanding superior and robust membranes. Herein, we report advanced OSN processes by designing three‐dimensional covalent organic framework (3D COF) membranes through moderated interfacial crystallization. Nanoporous supports work as the moderator allowing the crystallization of 3D COF membranes. The 3D COF features sub‐nanometer and anti‐swelling channels, affording a sharp selectivity to fine targets with an exceptionally high and stable methanol permeance. Thus‐synthesized membrane exhibits a record stability against high‐concentration feeds and long‐term operation for ≈1000 h. Moreover, we unambiguously demonstrate that our membrane holds excellent practicality in purifying active pharmaceutical ingredients from organic liquids. This work reveals the great potential of distinctive 3D COFs in producing prominent OSN membranes for industrial applications. [ABSTRACT FROM AUTHOR]