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1. Organocatalytic synthesis of β-enaminyl radicals as the single-electron donors for phenyliodine(III) dicarboxylates: Direct one-pot alkylation-aminoxidation of styrenes

   https://doi.org/10.1039/D2OB01826H  

   Sakkani, Nagaraju; Jha, Dhiraj Kumar; Sadiq, Nouraan; Zhao, John C.-G. (April 2023, Organic & Biomolecular Chemistry)

   A direct one-pot alkylation-aminoxidation of styrene derivatives was achieved by using in-situ-generated alkyl and N-oxyl radicals. The corresponding O-alkylated hydroxylamine derivatives were obtained in moderate to good yields. The reaction features the generation of the alkyl radicals from phenyliodine(III) dicarboxylates via an organocatalytic process, the use of phenyliodine(III) dicarboxylates as the source of the alkyl radicals and the oxidant for the generation of the N-oxyl radicals, and the first generation of the β-enaminyl radicals via a HAT process and their use as the single-electron donors. 

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2. Interfacial structural crossover and hydration thermodynamics of charged C ₆₀ in water

   https://doi.org/10.1039/c8cp05422c  

   Sarhangi, Setare Mostajabi; Waskasi, Morteza M.; Hashemianzadeh, Seyed Majid; Matyushov, Dmitry V. (October 2018, Physical Chemistry Chemical Physics)

   Classical molecular dynamics simulations of the hydration thermodynamics, structure, and dynamics of water in hydration shells of charged buckminsterfullerenes are presented in this study. Charging of fullerenes leads to a structural transition in the hydration shell, accompanied by creation of a significant population of dangling O–H bonds pointing toward the solute. In contrast to the well accepted structure–function paradigm, this interfacial structural transition causes nearly no effect on either the dynamics of hydration water or on the solvation thermodynamics. Linear response to the solute charge is maintained despite significant structural changes in the hydration shell, and solvation thermodynamic potentials are nearly insensitive to the altering structure. Only solvation heat capacities, which are higher thermodynamic derivatives of the solvation free energy, indicate some sensitivity to the local hydration structure. We have separated the solvation thermodynamic potentials into direct solute–solvent interactions and restructuring of the hydration shell and analyzed the relative contributions of electrostatic and nonpolar interactions to the solvation thermodynamics. 

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3. Molecular properties affecting the hydration of acid–base clusters

   https://doi.org/10.1039/d1cp01704g  

   Myllys, Nanna; Myers, Deanna; Chee, Sabrina; Smith, James N. (June 2021, Physical Chemistry Chemical Physics)

   In the atmosphere, water in all phases is ubiquitous and plays important roles in catalyzing atmospheric chemical reactions, participating in cluster formation and affecting the composition of aerosol particles. Direct measurements of water-containing clusters are limited because water is likely to evaporate before detection, and therefore, theoretical tools are needed to study hydration in the atmosphere. We have studied thermodynamics and population dynamics of the hydration of different atmospherically relevant base monomers as well as sulfuric acid–base pairs. The hydration ability of a base seems to follow in the order of gas-phase base strength whereas hydration ability of acid–base pairs, and thus clusters, is related to the number of hydrogen binding sites. Proton transfer reactions at water–air interfaces are important in many environmental and biological systems, but a deeper understanding of their mechanisms remain elusive. By studying thermodynamics of proton transfer reactions in clusters containing up to 20 water molecules and a base molecule, we found that that the ability of a base to accept a proton in a water cluster is related to the aqueous-phase basicity. We also studied the second deprotonation reaction of a sulfuric acid in hydrated acid–base clusters and found that sulfate formation is most favorable in the presence of dimethylamine. Molecular properties related to the proton transfer ability in water clusters are discussed. 

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4. Homoleptic octahedral Co ^II complexes as precatalysts for regioselective hydroboration of alkenes with high turnover frequencies

   https://doi.org/10.1039/d3ra06113b  

   Zhang, Guoqi; Zeng, Haisu; Zadori, Nora; Marino, Camila; Zheng, Shengping; Neary, Michelle C. (September 2023, RSC Advances)

   Monoprotonated homoleptic complex of cobalt(ii) with 4′-pyridyl-2,2′;6′,2′′-terpyridine ligand is an efficient precatalyst for hydroboration of styrene derivatives with Markovnikov selectivity, displaying turnover frequencies up to 47 000 h⁻¹. 

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5. Synthesis of α‐Sulfonyl Ketones through a Salicylic Acid‐Catalyzed Multicomponent Reaction Involving Arylsulfonation and Oxidation

   https://doi.org/10.1002/slct.202104138  

   Sakkani, Nagaraju; Jakkampudi, Satish; Sadiq, Nouraan; Zhao, John_C‐G (December 2021, ChemistrySelect)

   Abstract The direct synthesis of α‐sulfonyl ketones was accomplished by a multicomponent reaction of styrene derivatives, anilines,t‐butyl nitrite, 1,4‐diazabicyclo[2.2.2]octane‐sulfur dioxide (DABSO), and oxygen catalyzed by salicylic acid. The aryl radicals generated from aniline derivatives andt‐butyl nitrite under the catalysis of salicylic acid was sulfonylated by DABSO to generate the arylsulfonyl radicals, which reacted further with styrenes, and then oxidized by oxygen to give the title compounds. Under the optimized conditions, the title compounds were obtained in good yields at ambient temperature within 1.5–2 h. 

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