Rare-earth,nitrogen-rich,oxygen heterocyclic supramolecular compounds(Nd,Sm,and Eu):Synthesis,structure,and catalysis for ammonium perchlorate

Three novel rare-earth,nitrogen-rich and oxygen heterocyclic supramolecular complexes,namely[Nd(BTF)_(2)(H_(2)O)_(5)]_(n),[Sm(BTF)_(2)(H_(2)O)_(5)]_(n),and[Eu(BTF)_(2)(H_(2)O)_(5)]_(n),were synthesized.A single crystal was obtained by the solvent evaporation method,and the structure and coordination mode of metal complexes were determined by single crystal X-ray diffraction.Results show that the supramolecular complexes contain many hydrogen bonds and thus have good thermal stability(T_(dec)>540 K).The thermal decomposition of ammonium perchlorate(AP)catalyzed by the complexes was investigated by differential thermal analysis,which reveals a pre-eminent catalytic effect on AP.The high temperature decomposition peak of AP can be advanced by nearly 90 K at the amount of added complexes of 10 wt%,and the activation energy of AP descent range is from 70 to 150 kJ/mol.The other properties were fully characterized through elemental analysis and Fourier transform infrared spectroscopy.

Synthesis of[60]Fullerene-Fused Allylbenzofurans via Palladium-Catalyzed Migration Reaction

Chemical functionalization of fullerenes has been an important topic in fullerene chemistry. Herein, an unprecedented Pd-catalyzed migration reaction of [60]fullerene with allyloxy-tethered aryl iodides is present for the preparation of novel [60]fullerene-fused allylbenzofurans. The use of 1,2-bis(diphenylphosphino)benzene (DPPBz) as a ligand is crucial for the success of the transformation. The reaction shows high chemo- and regioselectivity, and is flexible with regard to allyl-migration site, providing a new and efficient approach to rare [60]fullerene-fused benzofurans. Control experiments disclose that the reaction most probably undergoes a sequential C—O bond cleavage/allyl-migration/intermolecular cycloaddition cascade process.

Realizing Stable Carbonate Electrolytes in Li-O_(2)/CO_(2)Batteries

The increasing demand for high-energy storage systems has propelled the development of Li-air batteries and Li-O_(2)/CO_(2)batteries to elucidate the mechanism and extend battery life.However,the high charge voltage of Li2CO3 accelerates the decomposition of traditional sulfone and ether electrolytes,thus adopting high-voltage electrolytes in Li-O_(2)/CO_(2)batteries is vital to achieve a stable battery system.Herein,we adopt a commercial carbonate electrolyte to prove its excellent suitability in Li-O_(2)/CO_(2)batteries.The generated superoxide can be captured by CO_(2)to form less aggressive intermediates,stabilizing the carbonate electrolyte without reactive oxygen species induced decomposition.In addition,this electrolyte permits the Li metal plating/stripping with a significantly improved reversibility,enabling the possibility of using ultra-thin Li anode.Benefiting from the good rechargeability of Li2CO3,less cathode passivation,and stabilized Li anode in carbonate electrolyte,the Li-O_(2)/CO_(2)battery demonstrates a long cycling lifetime of 167 cycles at 0.1 mA·cm^(-2)and 0.25 mAh·cm^(-2).This work paves a new avenue for optimizing carbonate-based electrolytes for Li-O_(2)and Li-O_(2)/CO_(2)batteries.

Activated Anilide in Heterocyclic Synthesis： Synthesis of New Dihydropyridines, Dihydropyridazines and Thiourea Derivatives

A series of new dihydropyridines, butanamide, dihydropyridazines and thiourea derivatives have been prepared through the reactions of 3-aminopyridine （1） and N-（pyridin-3-yl）-3-（pyridin-3-ylimino）butanamide 3 with some electrophilic reagents, aryl diazonium salts and isothiocyanates. Elementary analysis, MS, IR, and 1H NMR spectra confirmed the identity of the products.

Diversity-Oriented Synthesis of Flavones and Isoflavones via Palladium/Norbornene Cooperative Catalysis

Flavones and isoflavones are recognized as privileged heterocyclic scaffolds for the preparation of bioactive compounds.Efficient methods to access these heterocycles are in urgent need.Herein,we report diversity-oriented synthesis of flavones and isoflavones from 3-iodochromones via palladium/norbornene cooperative catalysis.The success of this research relies on the use of a unique bridge-head ester modified norbornene derivative as the mediator.Salient features of this include readily available starting materi-als regarding 3-iodochromones,ortho-C-H arylating and alkylating reagents and ipso-terminating reagents,broad substrate scope,good chemoselectivity,good step-economy and scalability.A large number of structurally diversified flavones,isoflavones and 2,3-diarylated chromones can be quickly prepared in a predictable manner.As showcased by the efficient formal synthesis of um-bralisib,this chemistry can be treated as another valuable addition to the toolbox of medicinal chemists.