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Abstract The chemical reduction of a bilayer spironanographene,spiro‐NG(C₁₃₇H₁₂₀), with Na and K metals in the presence of [2.2.2]cryptand to yield [Na⁺(2.2.2‐cryptand)](C₁₃₇H₁₂₁⁻) (1) and [K⁺(2.2.2‐cryptand)](C₁₃₇H₁₂₁⁻) (2), respectively, is reported. X‐ray crystallography reveals the formation of a new “naked” anion (spiro‐NG_H⁻), in which spirocyclic ring cleavage and subsequent hydrogenation have occurred. Density Functional Theory (DFT) calculations suggest that the generation of the radical anion of the parent nanographene (spiro‐NG^•−), upon electron acceptance from Na and K metals, induces the cleavage of the strained spirobifluorene core. The resulting spin density localizes on a particular carbon atom, previously attached to the spiranic sp³carbon atom, facilitating a site‐specific hydrogenation to afford (spiro‐NG_H⁻). The electrostatic potential map of this anion reveals electron density concentrated at the five‐membered ring of the readily formed indenyl fragment, thus enhancing the aromaticity of the system. Furthermore, nuclear magnetic resonance (NMR) and UV–vis absorption spectroscopy experiments allowed to follow the in situ reduction and hydrogenation processes in detail. 

The stepwise reduction by 1–3 electrons of a π-expanded pyracylene with K and Rb reveals that in-build core asymmetry affects the spin-density distribution in the mono- and trianion radicals, as confirmed by EPR spectroscopy and DFT calculations. 

A heterometallic single-source molecular precursor Li2Mn2(tbaoac)6 (1 , tbaoac = tert -butyl acetoacetato) has been specifically designed to achieve the lowest decomposition temperature and a clean conversion to mixed-metal oxides. The crystal structure of this tetranuclear molecule was determined by single crystal X-ray diffraction, and the retention of heterometallic structure in solution and in the gas phase was confirmed by nuclear magnetic resonance spectroscopy and mass spectrometry, respectively. Thermal decomposition of this precursor at the temperatures as low as 310 oC resulted in a new metastable oxide phase formulated as lithium-rich, oxygen-deficient spinel Li1.5Mn1.5O3.5. This formulation was supported by a comprehensive suite of techniques including thermogravimetric/differential thermal analysis, elemental analysis, inductively coupled mass spectrometry, iodometric titration, X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy studies, and Rietveld refinement from powder X-ray diffraction data. Upon heating to about 400 oC, this new low-temperature phase disproportionates stoichiometrically, gradually converting to layered Li2MnO3 and spinel Li1+x Mn2-x O4 (x < 0.5). Further heating to 750 oC results in formation of thermodynamically stable Li2MnO3 and LiMn2O4 phases. 

A new supramolecular tecton is designed that has the unique potential of assembling well-ordered supramolecular complexes by forming five directional hydrogen bonds at a time. It ensures an ordered distribution of inorganic halometallate anions. 

A long-standing issue about the correct identification of an important starting reagent, iron(III) hexafluoroacetylacetonate, Fe(hfac)₃(1), has been resolved. Thetris-chelated mononuclear complex was found to crystallize in two polymorph modifications which can be assigned as the low-temperature (1-L) monoclinicP2₁/nand the high-temperature (1-H) trigonalP\overline{3}. Low-temperature polymorph1-Lwas found to transform to1-Hupon sublimation at 44 °C. Two modifications are clearly distinguished by powder X-ray diffraction (PXRD), single-crystal X-ray diffraction, differential scanning calorimetry (DSC), and melting-point measurements. On the other hand, the two forms share similar characteristics in direct analysis in real-time mass spectrometry (DART-MS), attenuated total reflection (ATR) spectroscopy, and some physical properties, such as color, volatility, sensitivity, and solubility. Analysis of the literature and some of our preliminary data strongly suggest that the appearance of two polymorph modifications for trivalent metal (both transition and main group) hexafluoroacetylacetonates is a common case for several largely used complexes not yet accounted for in the crystallographic databases. 

Two-fold reduction of a vertically expanded functionalized pentacene with Na metal is accompanied by a loss of diatropicity in the resulting dianion and engagement of side groups in sodium ion coordination. 

A unique trimeric radical cation with unequal charge distribution is obtained by chemical oxidation of triphenylene with GaCl₃. XRD determined structure is combined with computational modeling showing stabilizing pancake bonding in the π-stacks.