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581.
Treatment of the open‐cage fullerene C63H4NO2(Ph)2(Py)(N2C6H4) ( 1 ) with methanol at 150 °C results in an orifice‐enlargement reaction to give C69H8NO(CO2Me)(Ph)(Py)(N2C6H4) ( 2 ). The overall yield from C60 to isolated 2 is 6.1 % (four steps). Compound 2 contains a 24‐membered elliptic orifice that spans 8.45 Å along the major axis and 6.37 Å along the minor axis. The skeleton of 2 resembles the hypothetic C60H10 (5,5)‐carbon nanotube endcap. The cup‐shaped structure of 2 is able to include water, hydrogen cyanide, and acetylene, forming H2O@ 2 , HCN@ 2 , and C2H2@ 2 , respectively. The molecular structures of H2O@ 2 and HCN@ 2 have been determined by X‐ray crystallography. The 1H NMR spectra reveal substantial upfield shifts for the endohedral species, such as δ=?10.30 (for H2O), ?2.74 and ?14.26 (for C2H2), and ?1.22 ppm (for HCN), owing to the strong shielding effects of the fullerene cage.  相似文献   
582.
Inorganic red-NIR emissive materials are particularly relevant in many fields like optoelectronic, bioimaging or solar cells. Benefiting from their emission in devices implies their integration in easy-to-handle materials like liquid crystals, whose long-range ordering and self-healing abilities could be exploited and influence emission. Herein, we present red-NIR emissive hybrid materials obtained with phosphorescent octahedral molybdenum cluster anions electrostatically associated with amphiphilic guanidinium minidendrons. Polarized optical microscopy and X-ray analysis show that while the minidendron chloride salts self-organize into columnar phases, their association with the dianionic metal cluster leads to layered phases. Steady-state and time-resolved emission investigations demonstrate the influence of the minidendron alkyl chain length on the phosphorescence of the metal cluster core.  相似文献   
583.
An additive-free nickel-catalyzed α-allylation of aldehydes with allyl alcohol is reported. The reaction is promoted by 1 mol % of in situ formed nickel complex in methanol, and water is the sole by-product of the reaction. The experimental conditions allow the conversion of various α-branched aldehydes and α,β-unsaturated aldehydes as nucleophiles. The same catalyst and reaction conditions enabled a tandem aldol condensation of aldehyde/α-allylation reaction.  相似文献   
584.
Removal of heavy metals from drinking water sources and rivers is of strategic health importance and is essential for sustainable ecosystem development, in particular in polluted areas around the globe. In this work, new hybrid inorganic-organic material adsorbents made of ortho- (Si-o-OR) or para-Schiff base silica (Si-p-OR) were synthesized and characterized in depth. These hybrid adsorbents show a high selectivity to Cu(II), even in the presence of competing heavy metals (Zn(II), Cd(II), and Pb(II)), and also demonstrate great reusability after five adsorption-desorption cycles. Maximum sorption capacity for Cu(II) was found for Si-o-OR (79.36 mg g−1) and Si-p-OR (36.20 mg g−1) in no less than 25 min. Energy dispersive X-ray fluorescence and Fourier transform-infrared spectroscopy studies demonstrate that this uptake occurs due to a chelating effect, which allows these adsorbents to trap Cu(II) ions on their surfaces; this result is supported by a theoretical study for Si-o-OR. The new adsorbents were tested against real water samples extracted from two rivers from the Oriental region of Morocco.  相似文献   
585.
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