The protonolysis reaction of the germanium(II) amide Ge[N(SiMe3)2]2 with calix[4]arene and calix[8]arene furnishes the two germanium(II) calixarene complexes {calix[4]}Ge2 and {calix[8]}Ge4, respectively, which have been crystallographically characterized. The calix[4]arene complex contains a Ge2O2 rhombus at the center of the molecule and is one of the only four germanium(II) calix[4]arenes that have been structurally characterized. The calix[8]arene species is the first reported germanium calix[8]arene complex, and it exhibits an overall bowl-shaped structure which contains two Ge2O2 fragments. The latter complex reacts with Fe2(CO)9 to yield an octairon compound, which has also been structurally characterized and contains four GeFe2 triangles arranged around the macrocyclic ring. The germanium(II) centers are oxidized to germanium(IV) in this process, with concomitant reduction of the neutral diiron species to Fe2(CO)(8)2- anions.

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The outcome of the reaction of the bulky metal(II) amides M[N(SiMe3)2]2. nTHF (M = Be, Zn, Ge, Sn, n = 0; M = Mg, Ca, n = 2) with (R)-3,3'-bis(trimethylsilyl)-1,1'-bi-2,2'-naphthol ((R)-1) or (S)-3,3'-bis(dimethylphenylsilyl)-1,1'-bi-2,2'-naphthol ((S)-9) depends on the identity of the metal and the nature of the 3,3'-substituents. When M = Be, Zn, or Ge, these amides serve as useful silylation agents that convert only one of the equivalent hydroxyl groups of the binaphthol (R)-1 to a trimethylsilyl ether, whereas the reactions of (R)-1 with the Mg, Ca, or Sn amides generate a polynuclear complex. The reaction pathway for these interconversions was qualitatively monitored using NMR ((1)H and (9)Be) spectroscopy. Treatment of Ge[N(SiMe3)2] 2 with (S)-9 yields both a silyl ether and the chelated germanium(II) binaphthoxide (S)-[Ge{O2C20H10(SiMe2Ph)2-3,3'}{NH3}], which was structurally characterized.

The origins of spin exchange in crystalline thin films of Copper Octabutoxy Phthalocyanine (Cu-OBPc) are investigated using Magnetic Circular Dichroism (MCD) spectroscopy. These studies are made possible by a solution deposition technique which produces highly ordered films with macroscopic grain sizes suitable for optical studies. For temperatures lower than 2 K, the contribution of a specific state in the valence band manifold originating from the hybridized lone pair in nitrogen orbitals of the Phthalocyanine ring, bears the Brillouin-like signature of an exchange interaction with the localized d-shell Cu spins. A comprehensive MCD spectral analysis coupled with a molecular field model of a σπ − d exchange analogous to sp-d interactions in Diluted Magnetic Semiconductors (DMS) renders an enhanced Zeeman splitting and a modified g-factor of −4 for the electrons that mediate the interaction. These studies define an experimental tool for identifying electronic states involved in spin-dependent exchange interactions in organic materials.

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Iridium complexes bearing a bis(phosphinite) pincer ligand are highly active for the dehydrocoupling of phenylsilane, comparable to other catalysts for this reaction. Interestingly, this catalysis produces primarily a single product, the decasilane ring cyclo-(PhSiH) 10 in what is unusually high selectivity for a single product in silane dehydrocoupling.

Developing methods to rapidly screen for novel synthetic 2-benzylbenzimidazole opioids, also known as nitazenes, has become increasingly important due to their high potency. These compounds have potency comparable or exceeding that of fentanyl by up to 10 times and have been implicated in approximately 5% of all drug overdose deaths in the United States in 2021. This paper details the authenticity determination of suspect tablets and the identification of three nitazene analogs (N-pyrrolidino etonitazene, isotonitazene, and etodesnitazene) in suspect tablets seized at a mail facility using Raman and surface-enhanced Raman scattering (SERS) with handheld devices, portable Fourier transform infrared spectrometer (FT-IR), and a direct analysis in realtime ambient ionization coupled to a thermal desorption unit and a mass spectrometer (DART-TD-MS). These methods are rapid and excellent for screening opioids in suspect tablets but could not fully determine the exact structure of some of the nitazene analogs present due to spectral similarities or similar fragmentation patterns.Liquid chromatography-mass spectrometry (LC-MS) confirmed the presence of these nitazene compounds in addition to other opioids/drugs that were in trace quantities. The quantitative high-performance liquid chromatography coupled with ultraviolet (HPLC-UV) detection experiments determined that the suspect tablets contained an average of 0.817 mg of N-pyrrolidino etonitazene per tablet. The results obtained reveal that the simultaneous deployment of these complementary and orthogonal portable analytical techniques as part of a workflow allows suspect tablets to be screened and nitazene-type drugs to be identified in suspect counterfeit tablets at remote sampling sites.

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