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Abstract An efficient and convergent (4+1)‐cycloaddition strategy toward the construction of spirooxindole benzofurans that involves the intermediacy of an isatin‐derived oxyphosphonium enolate is presented. Mechanistic investigations employing in situ NMR analysis of the reaction mixture revealed a correlation between phosphonium enolate structure and product distribution that was heavily influenced by the solvent and reaction temperature. 

Abstract Seawater desalination plays a critical role in addressing the global water shortage challenge. Directional Solvent Extraction (DSE) is an emerging non-membrane desalination technology that features the ability to utilize very low temperature waste heat (as low as 40 °C). This is enabled by the subtly balanced solubility properties of directional solvents, which do not dissolve in water but can dissolve water and reject salt ions. However, the low water yield of the state-of-the-art directional solvent (decanoic acid) significantly limits its throughput and energy efficiency. In this paper, we demonstrate that by using ionic liquid as a new directional solvent, saline water can be desalinated with much higher production rate and thus significantly lower the energy and exergy consumptions. The ionic liquid identified suitable for DSE is [emim][Tf₂N], which has a much (~10×) higher water yield than the currently used decanoic acid. Using molecular dynamics simulations with Gibbs free energy calculations, we reveal that water dissolving in [emim][Tf₂N] is energetically favorable, but it takes significant energy for [emim][Tf₂N] ions to dissolve in water. Our findings may significantly advance the DSE technology as a solution to the challenges in the global water-energy nexus. 

Abstract Deregulation of dual‐specificity tyrosine phosphorylation‐regulated kinase 1A (DYRK1A) plays a significant role in developmental brain defects, early‐onset neurodegeneration, neuronal cell loss, dementia, and several types of cancer. Herein, we report the discovery of three new classes ofN‐heterocyclic DYRK1A inhibitors based on the potent, yet toxic kinase inhibitors, harmine and harmol. An initial in vitro evaluation of the small molecule library assembled revealed that the core heterocyclic motifs benzofuranones, oxindoles, and pyrrolones, showed statistically significant DYRK1A inhibition. Further, the utilization of a low cost, high‐throughput functional genomic in vivo model system to identify small molecule inhibitors that normalizeDYRK1Aoverexpression phenotypes is described. This in vivo assay substantiated the in vitro results, and the resulting correspondence validates generated classes as architectural motifs that serve as potential DYRK1A inhibitors. Further expansion and analysis of these core compound structures will allow discovery of safe, more effective chemical inhibitors of DYRK1A to ameliorate phenotypes caused by DYRK1A overexpression. 

A proline-squaraine ligand (Pro-SqEB) that demonstrates high levels of stereoselectivity in olefin cyclopropanations when anchored to a Rh2 II scaffold is introduced. High yields and enantioselectivities were achieved in the cyclopropanation of alkenes with diazo compounds in the presence of Rh2(Pro- SqEB)4. Notably, the unique electronic and steric design of this catalyst enabled the use of polar solvents that are otherwise incompatible with most RhII complexes. 

Abstract This study describes an apparatus for high-precision variable temperature measurement of liquid vapor pressure. The apparatus can be used to measure the vapor pressure using only 0.5 ml of the liquid sample. To evaluate the accuracy of the device measurement, water and 2-propanol are utilized as standard liquids, and their vapor pressure is measured with a maximum uncertainty of ∼1%. This apparatus can be replicated using inexpensive and commonly used laboratory fittings and fixtures, making it an indispensable tool for synthetic chemists and chemical engineers involved in the iterative synthesis of compounds, targeting different vapor–liquid equilibrium regimes.