Revisiting the Influence of Silver in Cationic Gold Catalysis: A Practical Guide

An excess amount of silver salt to generate cationic gold from a gold catalyst precursor such as L–Au–Cl almost always has adverse effects on the reactivity of the cationic gold catalyst. A preformed L–Au⁺X^– complex, generated by sonication followed by centrifugation, increases the reactivity in a gold catalyzed reaction. The adverse silver effect might be caused by the interaction of silver salts with gold intermediates

Designer HF-Based Fluorination Reagent: Highly Regioselective Synthesis of Fluoroalkenes and <i>gem</i>-Difluoromethylene Compounds from Alkynes

Hydrogen fluoride (HF) and selected nonbasic and weakly coordinating (toward cationic metal) hydrogen-bond acceptors (e.g., DMPU) can form stable complexes through hydrogen bonding. The DMPU/HF complex is a new nucleophilic fluorination reagent that has high acidity and is compatible with cationic metal catalysts. The gold-catalyzed mono- and dihydrofluorination of alkynes using the DMPU/HF complex yields synthetically important fluoroalkenes and <i>gem</i>-difluoromethlylene compounds regioselectively

(Radio)Fluoro-iodination of Alkenes Enabled by a Hydrogen Bonding Donor Solvent

We have developed a widely applicable (radio)fluoro-iodination of alkenes using readily available and easily handled KF (18F). The reactions exhibited high functional group tolerance and needed only an ambient atmosphere. Furthermore, the resulting product could be further functionalized with various nucleophiles

Sustainable Recycling of Benzoic Acid Production Waste: Green and Highly Efficient Methods To Separate and Recover High Value-Added Conjugated Aromatic Compounds from Industrial Residues

Industrial residues formed in the industrial production of benzoic acid by cobalt-catalyzed oxidation of toluene are traditionally disposed as waste materials and often burnt or buried. It therefore may become a significant source of environmental pollution. In this report, we describe simple techniques to obtain high value conjugated aromatic compounds, including 9-fluorenone, 6H-benzo­[c]­chromen-6-one, biphenyl-3-carboxylic acid, and biphenyl-4-carboxylic acid, from benzoic acid industrial residue using inexpensive alkalis and acids. The separation methods involve simple and mild procedures with high economic effectiveness and low environmental contamination