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Metal–organic layers stabilize Fe II or Co II -terpyridine diradical complexes to catalyze alkylazide C sp3 –H amination and benzylic C–H borylation, respectively.
PuL 2 and CeL 2 (L = N,N'-bis[(4,4'-diethylamino)salicylidene]-1,2-phenylenediamine) have been synthesized, and characterized by single crystal X-ray diffraction, UV/vis/NIR spectroscopy, and cyclic voltammetry. Furthermore, these studies reveal the enhanced stabilization of Pu(IV) versus Ce(IV) with this Schiff base, and quasi-reversible redox behavior only with the plutonium complex.
Synthesis, magnetic, and theoretical studies of a new family of mononuclear lanthanide complexes exhibiting the very rare cubic coordination geometry.
Uranium-in-cryptand complexes can be readily synthesized by reacting UI 3 with 2.2.2-cryptand.
Four novel Pu( iv ) nitrato chloro complexes were crystallographically characterized and the Pu–ligand bond nature was delineated computationally.
Structure-based simulations and pH-dependent spectra have been used to clarify the protonation preferences of bilin pigments in cryptophyte photosynthetic complexes.
Complexation of selenomaltol to transition metal ions promotes a zwitterionic resonance form.
The first uranium( iii ) phosphido complex is reported.
We report the solution and structural chemistry of nickel( ii ) complexes of the phosphine-oxime Ph 2 PC 6 H 4 -2-CH₌NOH (PCH₌NOH).
Reaction of CoCO 3 with α,α,α′,α′-tetramethyl-1,3-benzenedipropionic acid (H 2 esp) in EtOH forms the paddlewheel-type dimer Co 2 (esp) 2 (EtOH) 2 , which hydrolyzes in MeCN to give a bowl-shaped heptacobalt coordination cluster complex; both compounds display antiferromagnetic interactions between high-spin Co( ii ) ions.
Steric control of dioxygen activation is demonstrated through O 2 titration and isotopic labeling experiments for two Mn( ii ) complexes.
The ligand substituents have a major effect on the redox potentials, catalytic efficiency and robustness of the complexes in HER.
Metalloenzymes are remarkably active, specific, and efficient catalysts.Mimicking the active sites with organometallic complexes based on crystal structures has been a focus for many synthetic chemists. These surrogates have provided significant mechanistic insight into both the molecular complexes as well as the enzymes, however, one of the principle findings has been that just reproducing the active site is not adequate in reproducing the catalytic function. Specifically, the scaffold surrounding the active site plays a critical role in many aspects of catalysis, from positioning reactants optimally to positioning functional groups for reaction to creating the ideal environment for catalysis. Each of these can be controlled with both static positioning as well as small and large dynamics that can activate or control a specific part of the reaction. In this review, we will discuss the effect of organic/peptidic scaffolds, along with medium as an extension of the scaffold, and their varying impacts on catalytic reactivity.
Organic photovoltaics have reached high power conversion efficiencies (PCE) using non-fullerene acceptors (NFAs). However, the best NFAs tend to have complex syntheses, limiting scalability. Among polymer donors, regioregular poly(3-hexylthiophene) (P3HT) has the greatest potential for commercialization due to its simple synthesis and good stability, but PCEs have been limited. It is thus imperative to find scalable NFAs that give high PCE with P3HT. Herein we report a zinc( II ) complex of di(naphthylethynyl)azadipyrromethene (Zn(L2) 2 ) as a non-planar NFA that can be synthesized on the gram scale using inexpensive starting materials without chromatography column purification. The NFA has strong absorption in the 600–800 nm region. Time-dependent density-functional theory calculations suggest that the low-energy absorptions can be understood within a four-orbital model involving transitions between π-orbitals on the azadipyrromethene core. OPVs fabricated from P3HT:Zn(L2) 2 blends reached a PCE of 5.5%, and the PCE was not very sensitive to the P3HT:Zn(L2) 2 weight ratio. Due to its shape, Zn(L2) 2 shows isotropic charge transport and its potential as an electron donor is also demonstrated. The combination of simple synthesis, good PCE and photostability, and tolerance to the active material weight ratio demonstrates the potential of Zn(L2) 2 as an active layer material in OPVs.
A detailed photophysical study of binuclear complexes was performed using steady-state and time-resolved photoluminescence measurements at variable temperature. The results were compared with the prototypical [Ru(bpy) 3 ] 2+ .
A cobalt complex supported by the 2-(diisopropylphosphaneyl)benzenethiol ligand was synthesized and its electronic structure and reactivity were explored.
The synthesis, characterization, emission, and electronic spectroscopy for complexes of derivatives of 2-(1 H -imidazo[4,5- b ]phenazin-2-yl)phenol with uranyl (UO 2 2+ ) and copper (Cu 2+ ) are detailed.
Hydrogen bonding networks are vital for metallo-enzymes to function; however, modeling these systems is non-trivial. The development of 1st-row transition metal chloride complexes with intramolecular hydrogen-bonding interactions are detailed herein.