Synthesis of [Os(bpy)(py)(OH)](PF) substituted pyridine complexes; characterization of a singly bridged HO ligand.

Proton-coupled electron transfer (PCET) underpins energy conversion processes in biological systems and fuel-forming reactions. Interrogation of the dynamics of electron and proton transfer in PCET processes requires tunable models, with synthetic transition metal aquo complexes being particularly well-explored examples. A previous study on a PCET model, [Os(bpy)(py)(OH)] (bpy = 2,2'-bipyridine; py = pyridine), reported synthetic intractability which limits access to this class of models.

Fragment-Guided Genome Mining of Octacyclic Cyclophane Alkaloids from Fungi.

Nature uses compact but functionalized biosynthetic fragments as building blocks to generate complex natural products. To leverage this strategy for the discovery of natural products with new scaffolds, we performed genome mining to identify biosynthetic gene clusters (BGCs) in fungi that embed genes that can synthesize targeted fragments. The three-enzyme pathway that biosynthesizes the strained dityrosine cyclophane in the herquline A pathway was used to identify a large number of potential BGCs that may use the cyclophane as a fragment.

Toward liquid cell quantum sensing: Ytterbium complexes with ultranarrow absorption.

The energetic disorder induced by fluctuating liquid environments acts in opposition to the precise control required for coherence-based sensing. Overcoming fluctuations requires a protected quantum subspace that only weakly interacts with the local environment. We report a ytterbium complex that exhibited an ultranarrow absorption linewidth in solution at room temperature with a full width at half maximum of 0.

Atomically precise inorganic helices with a programmable irrational twist.

Helicity in solids often arises from the precise ordering of cooperative intra- and intermolecular interactions unique to natural, organic or molecular systems. This exclusivity limited the realization of helicity and its ensuing properties in dense inorganic solids. Here we report that Ga atoms in GaSeI, a representative III-VI-VII one-dimensional (1D) van der Waals crystal, manifest the rare Boerdijk-Coxeter helix motif.

Ultrafast Au(III)-Mediated Arylation of Cysteine.

Through mechanistic work and rational design, we have developed the fastest organometallic abiotic Cys bioconjugation. As a result, the developed organometallic Au(III) bioconjugation reagents enable selective labeling of Cys moieties down to picomolar concentrations and allow for the rapid construction of complex heterostructures from peptides, proteins, and oligonucleotides. This work showcases how organometallic chemistry can be interfaced with biomolecules and lead to a range of reactivities that are largely unmatched by classical organic chemistry tools.

Charge and Solvent Effects on the Redox Behavior of Vanadyl Salen-Crown Complexes.

The incorporation of charged groups proximal to a redox active transition metal center can impact the local electric field, altering redox behavior and enhancing catalysis. Vanadyl salen (salen = ,'-ethylenebis(salicylideneaminato)) complexes functionalized with a crown ether containing a nonredox active metal cation (V-Na, V-K, V-Ba, V-La, V-Ce, and V-Nd) were synthesized. The electrochemical behavior of this series of complexes was investigated by cyclic voltammetry in solvents with varying polarity and dielectric constant (ε) (acetonitrile, ε = 37.

Synthesis, structural studies, and redox chemistry of bimetallic [Mn(CO)] and [Re(CO)] complexes.

Manganese ([Mn(CO)]) and rhenium tricarbonyl ([Re(CO)]) complexes represent a workhorse family of compounds with applications in a variety of fields. Here, the coordination, structural, and electrochemical properties of a family of mono- and bimetallic [Mn(CO)] and [Re(CO)] complexes are explored. In particular, a novel heterobimetallic complex featuring both [Mn(CO)] and [Re(CO)] units supported by 2,2'-bipyrimidine (bpm) has been synthesized, structurally characterized, and compared to the analogous monomeric and homobimetallic complexes.

Reducing CO to HCO at Mild Potentials: Lessons from Formate Dehydrogenase.

The catalytic reduction of CO to HCO requires a formal transfer of a hydride (two electrons, one proton). Synthetic approaches for inorganic molecular catalysts have exclusively relied on classic metal hydrides, where the proton and electrons originate from the metal (via heterolytic cleavage of an M-H bond). An analysis of the scaling relationships that exist in classic metal hydrides reveal that hydride donors sufficiently hydridic to perform CO reduction are only accessible at very reducing electrochemical potentials, which is consistent with known synthetic electrocatalysts.

Intensified Electrocatalytic CO Conversion in Pressure-Tunable CO -Expanded Electrolytes.

Multimolar CO concentrations are achieved in acetonitrile solutions containing supporting electrolyte at relatively mild CO pressures (<5 MPa) and ambient temperature. Such CO -rich, electrolyte-containing solutions are termed as CO -eXpanded Electrolytes (CXEs) because significant volumetric expansion of the liquid phase accompanies CO dissolution. Cathodic polarization of a model polycrystalline gold electrode-catalyst in CXE media enhances CO to CO conversion rates by up to an order of magnitude compared with those attainable at near-ambient pressures, without loss of selectivity.