Henan Normal University

About: Henan Normal University is a education organization based out in Xinxiang, China. It is known for research contribution in the topics: Catalysis & Ionic liquid. The organization has 10863 authors who have published 11077 publications receiving 166773 citations.

Rh(III)-Catalyzed Mild Coupling of Nitrones and Azomethine Imines with Alkylidenecyclopropanes via C–H Activation: Facile Access to Bridged Cycles

Abstract: Bridged cycles are an important class of structural motif in various biologically active molecules. Rh(III)-catalyzed C–H activation of nitrones and azomethine imines in the context of dipolar addition with alkylidenecyclopropanes (ACPs) have been realized. By taking advantage of the ring strain in ACPs, the reaction with aryl nitrones delivered bridged [3.2.1] bicyclic isoxazolidines, and reaction with azomethine imines afforded bridged tricyclic pyrazolones under the same conditions, where both the nitrone and azomethine imine act as a dipolar directing group. All the reactions occurred under mild conditions with broad substrates scope, high efficiency, and >20:1 diastereoselectivity. The synthetic applications of this protocol have also been demonstrated.

Selective separation of protein and saccharides by ionic liquids aqueous two-phase systems

Abstract: In the present work, it was found that aqueous solution of a hydrophilic ionic liquid (IL), 1-butyl-3-methylimidazolium dicyanamide ([C4mim][N(CN)2]), could be separated into an aqueous two-phase system (ATPS) by inorganic salts such as K2HPO4 and K3PO4. The top phase is IL-rich, while the bottom phase is phosphate-rich. It was shown that 82.7%–100% bovine serum albumin (BSA) could be enriched into the top phase and almost quantitative saccharides (arabinose, glucose, sucrose, raffinose or dextran) were preferentially extracted into the bottom phase in a single-step extraction by [C4mim][N(CN)2] + K2HPO4 ATPS. The extraction efficiency of BSA from the aqueous saccharide solutions was influenced by the molecular structure of saccharides. The conductivity, dynamic light scattering (DLS) and transmission electron microscopy (TEM) were combined to investigate the microstructure of the IL-rich top phase and the possible mechanism for the selective separation. It is suggested that the formation of the IL aggregate and the IL aggregate-BSA complex plays a significant role in the separation of BSA from aqueous saccharide solutions. This is the first example for the selective separation by ILs-based ATPSs. It is expected that these findings would have potential applications in bio-analysis, separation, and IL recycle.