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The earliest endohedral trianion captured: Sc3N@C80(CF3)2 (see figure) exhibits three reversible reductions and two reversible oxidations and affords the facile age group of the monocation, monoanion, and trianion in solution, which can be characterized by ESR and absorption spectroscopy. This is the first off delay that such a broad trade mark Aga of charged states of any endohedral fullerene has been spectroscopically characterized <<>>

An operative convey toward functionalised cyclic ethers: Computational mechanistic analysis is indicative of an operative Ln[bond]O [sigma]-bond insertion means with turnover-limiting cyclisation for intramolecular hydroalkoxylation of allenyl alcohols (see scheme) <<>>

Marrow in cage: By using a DFT-based basin-hopping method, we create putative extensive minima for three gold sulfide nanoclusters observed in body spectrometry that all manifest a symmetric core-in-cage structure: a metallic Au centre centre a cage with S as vertices and Au at the edges (see figure). This core-in-cage building is unique from magnitude gold sulfide. This work fills the acquaintanceship gap regarding the edifice of gold sulfide nanoclusters at [ap]1 nm <<>>

By using Car-Parrinello molecular dynamics (CPMD) simulations we cause simulated a mechanically induced redox reaction. Foregoing single-molecule atomic exact microscopy (AFM) experiments demonstrated that the reduction of disulfide bonds in proteins with the decrepit reducing envoy dithiothreitol depends on a mechanical destabilization of the breaking linkage. With reactive molecular dynamics simulations the solitary select steps of the reaction mechanism can be elucidated and the gesture of the electrons can be monitored. The simulations show that the redox reprisal consists of the heterolytic cleavage of the S[bond]S cohere followed by a sequence of proton transfers <<>>

3[prime],5[prime]-Dimethoxybenzoin (DMB) is a bichromophoric group that has widespread application as a well productive photoremovable protecting agglomeration (PRPG) for the release of discrete practical groups. The photodeprotection of DMB phototriggers is remarkably clean, and is accompanied by the forming of a biologically cordial cyclization product, 3[prime],5[prime]-dimethoxybenzofuran (DMBF). The underlying structure of the DMB deprotection and cyclization has, however, until now remained unclear. Femtosecond momentary absorption (fs-TA) spectroscopy and nanosecond time-resolved resonance Raman (ns-TR3) spectroscopy were employed to ascertain the impermanent species directly, and explore the high-powered transformations confusing in the noteworthy photoreactions for DMB diethyl phosphate (DMBDP) in acetonitrile (CH3CN). To assess the electronic sign and the role played by the discrete sub-chromophore, that is, the benzoyl, and the di-meta-methoxybenzylic moieties, for the DMBDP deprotection, comparative fs-TA measurements were also carried out for the insinuation compounds diethyl phosphate acetophenone (DPAP), and 3[prime],5[prime]-dimethoxybenzylic diethyl phosphate (DMBnDP) in the unmodified profitable. Relation of the fs-TA spectra reveals that the photoexcited DMBDP exhibits distinctly different ghostlike atypical and eager evolving from those of the specification compounds. This fact, combined with the interconnected steady-state ghostlike and density important theoretical results, strongly suggests the comportment in DMBDP of a expressive interaction middleman the two sub-chromophores, and that this interaction plays a governing impersonation in determining the nature of the photoexcitation and the reaction gutter of the consequent after photophysical and photochemical transformations. The ns-TR3 results and their correlation with the fs-TA spectra and dynamics provender deposition for a blockbuster concerted deprotection-cyclization mechanism for DMBDP in CH3CN. By monitoring the direct times of the transitory DMBF product, the cyclization time staunch was determined unequivocally to be [ap]1 ns. This indicates that there is little application for the long-lived intermediates (>10 ns) in giving the DMBF product, and excludes the stepwise system proposed in the brochures as the important pathway for the DMB cyclization reply. This arouse provides important new insights into the derivation of the 3[prime],5[prime]-dimethoxy replacement more for the DMB photodeprotection. It also helps to throw light on the many distinguishable views presented in previous mechanistic studies of the DMB PRPGs. In counting up to this, our fs-TA results on the relation compound DMBnDP in CH3CN furnish the before to the point observation (to the subdue of our knowledge) showing the preponderance of a prompt ([ap]2 ps) heterolytic reins cleavage after photoexcitation of meta-methoxybenzylic compounds. This provides perceptiveness into the long-term controversies reciprocity the photoinitiated dissociation system of mutual substituted benzylic compounds <<>>

The dinucleoside phosphate deoxycytidylyl-3[prime],5[prime]-deoxyguanosine (dCpdG) and deoxyguanylyl-3[prime],5[prime]-deoxycytidine (dGpdC) systems are amongst the largest to be well-thought-out by credible putative methods. Exploring electron attachment to these subunits of DNA celibate strands provides significant promotion toward ultimate predictions of the electron affinities of DNA apart strands. The adiabatic electron affinities of the oligonucleotides are build to be sequence dependent. Deoxycytidine (dC) on the 5[prime] end, dCpdG, has larger adiabatic electron affinity (AEA, 0.90 eV) than dC on the 3[prime] end of the oligomer (dGpdC, 0.66 eV). The geometric features, molecular orbital analyses, and indictment deployment studies for the organic anions of the cytidine-containing oligonucleotides protest that the superfluity electron in these anionic systems is dominantly located on the cytosine nucleobase moiety. The [pi]-stacking interaction between nucleobases G and C seems unattractive to improve the electron-capturing ability of the oligonucleotide dimers. The clout of the neighboring pinchbeck on the electron-capturing ability of cytosine should be attributed to the intensified proton accepting-donating interaction internuncio the bases. The distribute enquiry demonstrates that the vertical detachment energies (VDEs) of the total anions of the oligonucleotides DGpdC and DCpdG are significantly larger than those of the corresponding nucleotides. Consequently, reactions with low activation barriers, such as those for O[bond]C [sigma] checks and N-glycosidic bind breakage, puissance be expected for the thoroughgoing anions of the guanosine-cytosine muddled oligonucleotides <<>>

Simple pentafluorobenzyl-substituted ammonium and pyridinium salts with new anions can be conclusively obtained by treatment of the fountain-head amine or pyridine with the several pentafluorobenzyl halide. Hexafluorophosphate is introduced as the anion by brackish metathesis. In the case of the ammonium cured 4, freely co-crystallisation seems to smother in operation anion-[pi] interactions of bromide with the electron-deficient savoury system, whereas with salts 5 and 6 such interactions are observed despite the presence of distilled water. However, due to asymmetric hydrogen-bonding interactions with ammonium side chains, the anion of 5 is located close to the rim of the pentafluorophenyl set apart ([eta]1 interaction). In 6 the CH-anion hydrogen bonding is more symmetric and fixes the anion on top of the horn ([eta]6). A correspond to structure-controlling purport is observed in occasion of the 1,4-diazabicyclo[2.2.2]octane derivatives 7. Here the attitude of the anion (Cl, Br, I) is shifted according to the eventually of the low CH-halide interaction. The hexafluorophosphate 7 d reveals that this "non-coordinating" anion can be located on top of an fragrant [pi] practice. In the methyl-substituted pyridinium salts 9 and 10 abundant locations of the bromide anions with self-regard to the [pi] practice are observed. This is due to different conformations of the mono- versus disubstituted pyridine, which leads to diverse directions of the weak, but structurally important, HMe[bond]Br bonds <<>>

Li7PS6 and Li7PSe6 bound to to a class of new solids that express high Li+ mobility. A series of quaternary solid solutions Li7PS6-xSex (0[le]x[le]6) were characterised by X-ray crystallography and magic-angle spinning nuclear attractive resonance (MAS-NMR) spectroscopy. The high-temperature (HT) modifications were contrived by single-crystal investigations (both F4¯3m, Z=4, Li7PS6: a=9.993(1) Å, Li7PSe6: a=10.475(1) Å) and playing the regular argyrodite structures with strongly disordered Li atoms. HT-Li7PS6 and HT-Li7PSe6 transform reversibly into low-temperature (LT) modifications with ordered Li atoms. X-ray levigate diagrams express the structures of LT-Li7PS6 and LT-Li7PSe6 to be closely correlated to orthorhombic LT-[alpha]-Cu7PSe6. Individual crystals of the LT modifications are not available due to multiple twinning and generation of antiphase domains. The slow replacing of S by Se shows character instal preferences closely connected to the functionalities of the different types of chalcogen atoms (S, Se). High-resolution solid-state 31P NMR is a high method to specialize quantitatively between the distinct (PS4-nSen)3- neighbourhood pub environments. Their population order differs significantly from a statistical scenario, revealing a outright liking for P[bond]S greater than P[bond]Se bonding. This preference, shown for the series of LT samples, can be quantified in terms of an equilibrium undeviating specifying the move resistance SeP+S2-[rlhar2]SP+Se2-, until to crystallisation. The 77Se MAS-NMR spectra reveal that the chalcogen distributions in the defective and third coordination province of the P atoms are essentially statistical. The mass of crystallographically independent Li atoms in both LT modifications was analysed by means of 6Li{7Li} hoodwink polarisation sorcery oblique spinning (CPMAS) <<>>

Lanthanide-organic complexes of the accustomed strain [Ln{N(SiMe3)2}3] (Ln=La, Sm, Y, Lu) function as as useful precatalysts for the rapid, exo-selective, and highly regioselective tandem two-ply intramolecular hydroalkoxylation/cyclization of primary and second-line dialkynyl dialcohols to give over the corresponding bi-exocyclic enol ethers. Conversions are strongly selective with products distinctly unusual from those usually produced by old-fashioned transition metal or other catalysts, and the volume frequencies with some substrates are too considerable to decide accurately. The rates of concluding alkynl the bottle hydroalkoxylation/cyclization are significantly more precipitate than those of internal alkynyl alcohols, arguing that steric demands upper hand over the cyclization change country. The hydroalkoxylation/cyclizations of internal dialkynyl dialcohols give apart from E selectivity. The scale law for dialkynyl dialcohol hydroalkoxylation/cyclization is first-order in [catalyst] and zero-order in [alkynyl alcohol], as is observed for the organolanthanide-catalyzed hydroamination/cyclization of aminoalkenes, aminoalkynes, and aminoallenes, and the intramolecular single-step hydroalkoxylation/cyclization of alkynyl alcohols. An ROH/ROD kinetic isotope truly of 0.82(0.02) is observed for the tandem dead ringer hydroalkoxylation/cyclization. These mechanistic data involve turnover-limiting insertion of C[bond]C unsaturation into the Ln[bond]O bond, involving a tremendously organized mutation state, with subsequent, fast Ln-C protonolysis <<>>

meso-Triazolyl-appended ZnII-porphyrins were effortlessly of a mind by CuI-catalyzed 1,3-dipolar cycloaddition of benzyl azide to meso-ethynylated ZnII-porphyrin (click chemistry). In noncoordinating CHCl3 solvent, knee-jerk diet occurred to material tetrameric array (3)2 from meso-meso-linked diporphyrins 3, and dodecameric porphyrin squares (4)4 and (5)4 from the L-shaped meso-meso-linked triporphyrins 4 and 5. The structures of these assemblies were examined by 1H NMR spectra, absorption spectra, and their gel permeation chromatography (GPC) retention time. Furthermore, the structures of the dodecameric porphyrin squares (4)4 and (5)4 were probed by small- and wide-angle X-ray suggestion (SAXS/WAXS) measurements in mixture using a synchrotron begetter. Excitation-energy migration processes in these assemblies were also investigated in tabulate by using both steady-state and time-resolved spectroscopic methods, which revealed efficient excited-energy transmission (EET) between the meso-meso-linked ZnII-porphyrin units that occurred with time constants of 1.5 ps-1 for (3)2 and 8.8 ps-1 for (5)4 <<>>