Synthesis and Crystal Structure of 1,3-Bis[2-(pyrrol-2-carbonyloxy)ethoxy]Benzene

Abstract  

A new compound, 1,3-bis[2-(pyrrol-2-carbonyloxy)ethoxy]benzene (1), was synthesized and characterized by X-ray diffraction. The crystal is monoclinic, space group P2₁/c with a = 6.3571(7), b = 11.0416(11), c = 28.156(3) ?, b = 92.821(2), V = 1974.0(4) ?³, Z = 4, Dc = 1.293 g/cm³, F(000) = 808, μ = 0.097 mm⁻¹. The final R = 0.0395 and wR = 0.0927 for 3478 observed reflections with I > 2 σ(I), and R = 0.0660 and wR = 0.1058 for all reflections. The title compound assembles into 2-D structure through a catemer type N–H⋯O hydrogen bonding motif and further forms 3-D structure through C–H···O hydrogen bonds.     

高效医学传感钙钛矿材料研究进展

卤化物钙钛矿材料作为一种新型半导体材料,具有优异的光电转换特性、能级结构可调、易于加工、结构和尺寸以及形貌可调、改性后优异的生物相容性等优点,在医学检测传感器中具有广阔的应用前景。本综述讨论了钙钛矿材料在生物医学传感领域的研究进展,钙钛矿医学传感器能通过光电转换、全光转换、电催化等多种物理或化学机制实现传感,具有可灵活选择的器件结构、性能指标和信号传递方式,用于人体代谢物质、神经递质、癌症相关物质和药物等医学物质的检测。钙钛矿医学传感器将为未来的医工多学科融合提供新希望,加快医工融合发展。     

Synthesis of Single‐Crystalline Spinel LiMn2O4 Nanorods for Lithium‐Ion Batteries with High Rate Capability and Long Cycle Life

The long‐standing challenge associated with capacity fading of spinel LiMn₂O₄ cathode material for lithium‐ion batteries is investigated. Single‐crystalline spinel LiMn₂O₄ nanorods were successfully synthesized by a template‐engaged method. Porous Mn₃O₄ nanorods were used as self‐sacrificial templates, into which LiOH was infiltrated by a vacuum‐assisted impregnation route. When used as cathode materials for lithium‐ion batteries, the spinel LiMn₂O₄ nanorods exhibited superior long cycle life owing to the one‐dimensional nanorod structure, single‐crystallinity, and Li‐rich effect. LiMn₂O₄ nanorods retained 95.6 % of the initial capacity after 1000 cycles at 3C rate. In particular, the nanorod morphology of the spinel LiMn₂O₄ was well‐preserved after a long‐term cycling, suggesting the ultrahigh structural stability of the single crystalline spinel LiMn₂O₄ nanorods. This result shows the promising applications of single‐crystalline spinel LiMn₂O₄ nanorods as cathode materials for lithium‐ion batteries with high rate capability and long cycle life.     

Highly Enantioselective Ring‐Opening Reactions of Aziridines with Indole and Its Application in the Building of C3‐Halogenated Pyrroloindolines

A magnesium‐catalyzed asymmetric ring‐opening reaction of aziridine with indole has been realized by employing commercially available chiral ligands. Both of the enantiomers of the ring‐opening product could be obtained with good yields and a high level of enantioselectivity. The corresponding ring‐opening product could be further transformed to various types of enantioenriched C₃‐halogenated‐pyrroloindolines.     

High-pressure synthesis, crystal structure, and electromagnetic properties of CdRh2O4: an analogous oxide of the postspinel mineral MgAl2O4

The postspinel mineral MgAl(2)O(4) exists only under the severe pressure conditions in the subducted oceanic lithosphere in the Earth's deep interior. Here we report that its analogous oxide CdRh(2)O(4) exhibits a structural transition to a quenchable postspinel phase under a high pressure of 6 GPa at 1400 °C, which is within the general pressure range of a conventional single-stage multianvil system. In addition, the complex magnetic contributions to the lattice and metal nonstoichiometry that often complicate investigations of other analogues of MgAl(2)O(4) are absent in CdRh(2)O(4). X-ray crystallography revealed that this postspinel phase has an orthorhombic CaFe(2)O(4) structure, thus making it a practical analogue for investigations into the geophysical role of postspinel MgAl(2)O(4). Replacement of Mg(2+) with Cd(2+) appears to be effective in lowering the pressure required for transition, as was suggested for CdGeO(3). In addition, Rh(3+) could also contribute to this reduction, as many analogous Rh oxides of aluminous and silicic minerals have been quenched from lower-pressure conditions.