AI Article Synopsis

  • The study explored a method for chloride-bromide halogen exchange using a supported molten alkyl phosphonium catalyst, reacting alkyl chlorides and bromides.
  • The reaction reached near equilibrium under specific conditions in a tubular flow reactor at 150 °C and 1500 GHSV.
  • The catalyst, made through the impregnation of alumina or silica, demonstrated high stability over extended periods, and a potential catalytic cycle pathway was suggested.

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A modular approach was developed for the first catalytic asymmetric total syntheses of naturally occurring C30 terpene quinone methides and their non-natural stereoisomers, which feature the presence of an unprecedented spiro[4.4]nonane-containing 6-6-6-5-5-3 hexacyclic skeleton. Resting on a chiral phosphinamide-catalyzed enantioselective reduction of 2,2-disubstituted cyclohexane-1,3-dione, a concise route for the synthesis of enantioenriched 6-6 bicyclic fragment was developed.

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The most commonly used homogeneous catalyst for fatty acid esterification is a corrosive sulphuric acid. However, this requires costly investment in non-corrosive equipment, presents a safety risk, is time consuming, and increases effluent generation. In this study, inorganic 3D heteroborane cluster strong acids are employed for the first time as homogeneous catalysts.

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Pentafluoroorthotellurate Uncovered: Theoretical Perspectives on an Extremely Electronegative Group.

Inorg Chem

January 2025

Departamento de Química Física and Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), Universidad de Zaragoza, Zaragoza 50009, Spain.

Article Synopsis
  • The pentafluoroorthotellurate group (-OTeF, teflate) is a potent electron-withdrawing substitute for fluoride, known for its stability and size, which helps avoid bridging ligand behavior.
  • This study employs advanced Quantum Chemical Topology methods to analyze the electronic structure and bonding of the teflate group, comparing its electronegativity with halogens and investigating the interactions in various XOTeF systems.
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Article Synopsis
  • The study presents a method using TMSOTf to create spiroketal derivatives through hydroalkoxylation and cycloaddition reactions involving hydroxy cyclopropenes and aldehydes.
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Purpose: To assess and compare the diagnostic efficiency of histogram analysis of monochromatic and iodine images derived from spectral CT in predicting Ki-67 expression in gastric gastrointestinal stromal tumors (gGIST).

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