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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 A (4+1)‐cycloaddition is reported between 1,2‐dicarbonyls and aza‐o‐quinone methide precursors to access 2,3‐dihydroindoles bearing a tetra‐substituted carbon center. The utilization of dioxyphospholenes as carbene surrogates provided dihydroindoles in 20–90 % yield, wherein the electronic nature of the dioxyphospholene impacts its role in the reaction. 

Abstract (4+1)-Cyclizations are an underutilized disconnect for the formation of five-membered heterocyclic and carbocyclic frameworks. Herein we analyze methods employing oxyphosphonium enolates and RhII/PdII-metallocarbenes as C1 synthons in the presence of several four-atom components for the synthesis of 2,3-dihydrobenzofurans, 2,3-dihydroindoles, oxazolones, cyclopentenones, and pyrrolones. 1 Introduction 2 (4+1)-Cyclizations Employing Kukhtin–Ramirez-Like Reactivity 3 (4+1)-Cyclizations Employing a Cyclopropanation/Ring-Expansion Sequence 4 Pd-Catalyzed (4+1)-Cyclizations through Carbene Migratory Insertion/Reductive Elimination Processes 5 Summary 

Nucleophilic addition of phosphorus( iii ) agents to the electrophilic core of intensely colored squaraine dyes gives a bleached zwitterionic adduct in good to excellent yields (up to 99%) at room temperature. The process can be reversed by adding specific transition metal complexes with high phosphorous( iii ) affinity. 

Enantioselective quaternary carbon construction in the assembly of cyclopentenones employing a Rh II -catalyzed, formal [4+1]-cycloaddition is described. A Rh 2 ( S -TCPTTL) 4 -catalyzed cyclopropanation of a vinyl ketene with a disubstituted diazo compound initiates a stereoretentive, accelerated ring expansion to provide the cycloadduct in good to excellent yields and enantioselectivity.