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We report transition metal catalysis using novel chiral metal-chelating ligands featuring a silanol coordinating group and peptide-like aminoamide scaffold. The catalytic properties of the silanol ligand are demonstrated through an enantioselective Cu-catalyzed N–H insertion affording unnatural amino acid derivatives in high selectivity. Our investigations into the silanol coordination mode include DFT calculations, ligand structure investigations, and X-ray structure analyses, which support the formation of an H-bond stabilized silanol-chelating copper carbenoid complex. A p–p stacking interaction revealed by DFT calculations is proposed to enable selectivity for aryl diazoacetate substrates, overcoming some of the traditional limitations of using these substrates. 

The ternary phase, Yb14CdSb11, has been synthesized by flux and polycrystalline methods. The crystal structure is determined via single-crystal X-ray diffraction, revealing that it crystallizes in the Ca14AlSb11 structure type (I41/acd space group with unit cell parameters of a = 16.5962(2) & Aring; and c = 22.1346(5) & Aring;, 90 K, Z = 8, R1 = 2.65%, and wR2 = 4.58%). The polycrystalline form of the compound is synthesized from a stoichiometric reaction of Yb4Sb3, CdSb, Yb, and Sb. The elemental composition is confirmed using scanning electron microscopy and energy-dispersive spectroscopy, and phase purity is verified by powder X-ray diffraction. Thermoelectric measurements, including resistivity, Seebeck coefficient, thermal conductivity, Hall carrier concentration, and Hall mobility, are conducted from 300 to 1273 K. Yb14CdSb11 exhibits a peak zT = 0.90 at 1200 K. Carrier concentration and Hall mobility range from 6.99 x 1020-1.01 x 1021 cm-3 and 4.45-9.35 x 10-1 cm2 V-1 s-1, respectively. This carrier concentration is lower than that reported for the Zn or Mn analogs leading to a lower thermoelectric figure of merit at high temperatures. However, with appropriate doping, this phase should also be a promising p-type candidate for high-temperature energy conversion applications. 

Zintl phases containing rare-earth metals have gained attention due to their magnetic, electronic, and thermoelectric properties. Eu5.08Al3Sb6 is a new structure type (monoclinic space group C2/m) that can be described as a pseudorock-salt EuSb motif with the Eu-centered Sb octahedra at the origin of the unit cell, and on the C-face center, containing either Eu (8%) or an Al4 tetrahedron modeled as a dual tetrahedron (37.5%). The complete solid solution of Eu5.08-x Sr x Al3Sb6 can be prepared; however, the cation totals vacillate from 5 to 5.24 depending on the Al content. Al K-edge XANES shows a shift to higher energy relative to the Al metal but at slightly lower energy relative to AlSb, indicating an intermediate oxidation state closer to +3 than 0. The lack of an Al K-edge shift with the incorporation of Sr suggests that changes in Sr content do not have a meaningful impact on the electronics of the Al tetrahedra. Investigation of the solid solution structures provides evidence for classifying this structure type as a polar intermetallic phase with variable composition. Magnetization measurements were collected for the solid solution and show complex magnetic ordering with competing ferromagnetic and antiferromagnetic interactions as the Sr content increases. 

Abstract Herein we report the first transition metal‐catalyzed approach to the enantioenriched synthesis of cyclic sulfonimidamides relying on commercially available palladium catalysts and ligands. High‐throughput experimentation (HTE) was employed to identify the optimal catalyst system and solvent. The method is applied to a variety of saturated and unsaturated rings and exhibits the highest selectivity for 2‐substituted allyl electrophiles. The products are further elaborated to complex, tricyclic scaffolds. DFT experiments presented herein highlight the key ligand substrate interactions leading to the high levels of enantioselectivity. 

The relationshipE_pvs. ΔG_H− correlates the applied potential (E_p) needed to drive organohydride formation with the strength of the hydride donor that is formed: hydride transfer catalysis - as in enzymes like LarA - will be more energy efficient ifE_pis shifted anodically using kinetic effect. 

We report the ability to trap the dimer Au2(μ-dppe)2I2 (dppe is 1,2- bis(diphenylphosphino)ethane) with different separations between the three-coordinate gold ions in crystalline solvates. All of these solvates ((Au2(μ-dppe)2I2·4(CH2Cl2) (1), Au2(μ- dppe)2I2·2(CH2Cl2) (2), the polymorphs α-Au2(μ-dppe)2I2·2(HC(O)NMe2) (3) and β- Au2(μ-dppe)2I2·2(HC(O)NMe2) (4), and Au2(μ-dppe)2I2·4(CHCl3) (5)) along with polymeric {Au(μ-dppe)I}n·n(CHCl3) (6)) originated from the same reaction, only the solvent system used for crystallization differed. In the different solvates of Au2(μ-dppe)2I2, the Au···Au separation varied from 3.192(1) to 3.7866(3) Å. Computational studies undertaken to understand the flexible nature of these dimers indicated that the structural differences were primarily a result of crystal packing effects with aurophillic interactions having a minimal effect. 

Thermal Sn–C cleavage in the diarylstannylene Sn(Ar^iPr4)₂(Ar^iPr4= C₆H₃-2,6-(C₆H₃-2,6-iPr₂)₂) was used to generate ˙Sn(Ar^iPr4) and ˙Ar^iPr4radicals for alkyne arylstannylation.