Counter-anions (PhCO₂ ⁻, CF₃SO₃ ⁻, TsO⁻, and SbF₆ ⁻) perturb the stability of the tyrosinase's biomimetic model (P^T ). In this work, we showcase that the Gibbs energies, Cu₂O₂ and counter-anion distances, IGMH-based δG^Pair values, orbitals overlap between Cu₂O₂ and counter-anion, Cu₂O₂ bending angles, and distortion-interaction energies are computational indicators to predict the stability of P^T in presence of counter anions.

Abstract

It has been observed in literature that the stability of tyrosinase-mimicked μ-η²:η²-peroxo-dicopper(II) (P) can be perturbed in presence of counter-anions (CAs) such as PhCO₂ ⁻, CF₃SO₃ ⁻, TsO⁻ and SbF₆ ⁻. In this work, we unravel computational indicators using density functional theory to screen and study the stability of P in experimentally-reported cases. These indicators are Gibbs energies, geometrical parameters such as distances and angles, independent gradient model based on Hirshfeld partition (IGMH) generated data, orbitals’ overlap, and distortion-interaction (DI) energies. Our DFT computed Gibbs energies indicate that P is stable in case of PhCO₂ ⁻ and TsO⁻. CF₃SO₃ ⁻ allows P and its isoelectronic species bis-μ-oxo-dicopper (O) to coexist. SbF₆ ⁻ shows that O is in excess. Our indicators reveal that the stability of P in case of PhCO₂ ⁻ and TsO⁻ is due to the better placing of P and its CA, thus leading to better interactions and overlap of orbitals. Other indicator displays that the plane of Cu₂O₂ core in P is more bend in PhCO₂ ⁻ and TsO⁻ cases as compared to the plane in the other two cases. In addition, the IGMH-based indicator displays higher values in the case of PhCO₂ ⁻ and TsO⁻ than the other CAs.

A ruthenium pincer catalyzed direct synthesis of oximes from alcohols and hydroxyl amine hydrochloride salt is reported. Notably, the reaction requires only a catalyst and base, and water and liberated hydrogen are the only byproducts making this protocol attractive and environmentally benign.

Abstract

A catalytic method for the direct synthesis of oximes from alcohols and hydroxyl amine hydrochloride salt is reported. The reaction is catalyzed by a ruthenium pincer catalyst, which oxidizes alcohols involving amine-amide metal-ligand cooperation, and the in situ formed aldehydes condense with hydroxyl amine to deliver the oximes. Notably, the reaction requires only a catalyst and base; water and liberated hydrogen are the only byproducts, making this protocol attractive and environmentally benign.

Fragile hemiaminal ether linkages present in the backbone of koneramine ligands bound to copper(II) in stereoselectively self-assembled complexes were transformed into sturdy methylene linkages by late-stage ligand modification after coordination with the retention of coordination sphere.

Abstract

Fragile hemiaminal ether linkages present in the backbone of koneramines (L^ROR’), tridentate ligands, bound to copper(II) in stereoselectively self-assembled syn-[Cu(L^ROR’)X₂] complexes were transformed into sturdy methylene linkages to make corresponding rac-[Cu(L^RH)Cl₂] complexes by late-stage ligand modification after coordination with the retention of coordination sphere. The generality of stereoselective self-assembly of koneramine complexes is shown by utilising a number of metal ions, anions, amines, alcohols and thiols with complete characterisations.

An efficient ex-situ method for the amidation of carboxylic acids mediated by CDI has been disclosed herewith. This metal-free strategy is performed at ambient temperature and can be applied effectively for late-stage modification of amino acids and APIs.

Transition metal-catalyzed borylation involves the incorporation of boron-containing fragment to organic molecules. Recent advancements of C_(Ar)−B bond-forming reaction include the development of new catalyst systems and boron reagents that allow for efficient transformations, as well as more versatile applications in drug synthesis and materials sciences. Representative synthetic strategies have demonstrated the ability to synthesize complex molecules through the borylative pathway as a key synthetic step.

Abstract

Transition metal-catalyzed borylation has emerged as a powerful and versatile strategy for synthesizing organoboron compounds. These compounds have found widespread applications in various aspects, including organic synthesis, materials science, and medicinal chemistry. This review provides a concise summary of the recent advances in palladium- and rhodium-catalyzed borylation from 2013 to 2023. The review covers the representative examples of catalysts, substrates scope and reaction conditions, with particular emphasis on the development of catalyst systems, such as phosphine ligands, NHC-carbene, and more. The diverse array of borylative products obtained for further applications in Suzuki-Miyaura coupling, and other transformations, are also discussed. Future directions in this rapidly evolving field, with the goal of designing more efficient, selective borylation methodologies are highlighted, too.

Photoinitiated 6π-electrocyclization was developed as an efficiently strategy to construct vicinal quaternary carbons. Combined with homoallylic elimination, the 13,30-cyclodammarane skeleton of phainanoid F was constructed.

Abstract

In this paper, we report an efficient strategy for synthesizing the DEFGH rings of phainanoid F. The key to the construction of the 13,30-cyclodammarane skeleton of the molecule was a photo-induced 6π-electrocyclization and a homoallylic elimination. Notably, this is a rare example of using electrocyclization reaction to simultaneously construct two vicinal quaternary carbons in total synthesis. The strategy outlined here forms the basis of our total synthesis of Phainanoid F, and it could also serve as a generally applicable approach for synthesizing other natural products containing similar 13,30-cyclodammarane skeletons.

Three-arm star polymethacrylates with dual-phase (solution and solid-state) fluorescent emission were synthesized via ATRP using a triphenylamine-derived organoboron complex TAPA-BKI-3Br as initiator.

Abstract

Three-arm star polymethacrylates with dual-phase (solution and solid-state) fluorescent emission have been synthesized via atom transfer radical polymerization (ATRP) using a triphenylamine-derived organboron complex (TAPA-BKI-3Br) as initiator. The as-synthesized three-arm star polymethacrylates exhibited bright emission in both solution and the solid states due to the highly twisted structure and intramolecular charge transfer (ICT) effect of TAPA-BKI core, as well as the steric effect and restriction of intramolecular motions from the polymer arms. And the polymer chains have an important influence on the photophysical behavior of the as-synthesized three-arm star polymethacrylates in the aggregated state.

This work proposes a new facile, cost-effective, and safe preparation method for CoP loaded on N-doped carbon using inexpensive starting materials. The optimized ratio in the starting materials allowed CoP loaded on N-doped carbon to show high hydrogen evolution activity with 202 mV of overpotential at 10 mA/cm² and stability.

Abstract

The manufacture of efficient and low-cost hydrogen evolution reaction (HER) catalysts is regarded as a critical solution to achieve carbon neutrality. Herein, we developed an economical method to synthesize a CoP-anchored N-doped carbon catalyst via one-step pyrolysis using inexpensive starting materials (cobalt ion salt, phytic acid, and glycine). The size of the CoP nanoparticles was controlled by adjusting the Co/P ratio of the catalysts. Nanoscale CoP particles with adequate exposure to active sites were uniformly anchored on the surface of the conductive nitrogen-doped carbon substrate, ensuring the rapid transfer of electrons and species. When Co/P=0.89, the as-made catalyst exhibited outstanding HER activity, with an extraordinarily low overpotential of 202 mV at 10 mA cm⁻² and long-term stability.

This review describes the behaviour of vinyl radicals produced through photoredox catalysis and how different reactivity patterns have been achieved by manipulating its chemistry. The focus has been on constructing various valuable scaffolds through 1,1-difunctionalization, 1,2-difunctionalization, and cyclization reactions.

Abstract

Organic chemistry has seen a surge in visible-light-driven transformations, which offer unique reaction pathways and access to new synthetic possibilities. We aim to provide a comprehensive understanding of state-of-the-art photo-mediated alkyne functionalization, with a focus on the reactive behavior of vinyl radicals. This review outlines our contributions to the field, including developing new methods for forming carbon-carbon and carbon-heteroatom bonds.

PtNi/Sb_0.11SnO₂ with high durability was synthesized by adjusting the doping amount of antimony. The prepared PtNi/Sb_0.11SnO₂ retained excellent catalytic activity and hardly reduced half-wave potential in acidic conditions after 10,000 cycles, which displayed its high durability.

Abstract

Carbon-supported Pt is currently used as catalyst for oxygen reduction reaction (ORR) in fuel cells but is handicapped by carbon corrosion at high potential. Herein, a stable PtNi/SnO₂ interface structure has been designed and achieved by a two-step solvothermal method. The robust and conductive Sb-doped SnO₂ supports provide sufficient surfaces to confine PtNi alloy. Moreover, PtNi/Sb_0.11SnO₂ presents a more strongly coupled Pt-SnO₂ interface with lattice overlap of Pt (111) and SnO₂ (110), together with enhanced electron transfer from SnO₂ to Pt. Therefore, PtNi/Sb_0.11SnO₂ exhibits a high catalytic activity for ORR with a half-wave potential of 0.860 V versus reversible hydrogen electrode (RHE) and a mass activity of 166.2 mA mg_Pt ⁻¹@0.9 V in 0.1 M HClO₄ electrolyte. Importantly, accelerated degradation testing (ADT) further identify the inhibition of support corrosion and agglomeration of Pt-based active nanoparticles in PtNi/Sb_0.11SnO₂. This work highlights the significant importance of modulating metal-support interactions for improving the catalytic activity and durability of electrocatalysts.