Molecular perovskites are promising practicable energetic materials with easy access and outstanding performances. Herein, we reported the first comparative thermal research on energetic molecular perovskite structures of (C6H14N2)[NH4(ClO4)3], (C6H14N2)[Na(ClO4)3], and (C6H14ON2)[NH4(ClO4)3] through both calculation and experimental methods with different heating rates such as 2, 5, 10, and 20 °C/min. The peak temperature of thermal decompositions of (C6H14ON2)[NH4(ClO4)3] and (C6H14N2) [Na(ClO4)3] were 384 and 354 °C at the heating rate of 10 °C/min, which are lower than that of (C6H14N2)[NH4(ClO4)3] (401 °C). The choice of organic component with larger molecular volume, as well as the replacement of ammonium cation by alkali cation weakened the cubic cage skeletons; meanwhile, corresponding kinetic parameters were calculated with thermokinetics software. The synergistic catalysis thermal decomposition mechanisms of the molecular perovskites were also investigated based on condensed-phase thermolysis/Fourier-transform infrared spectroscopy method and DSC-TG-FTIR-MS quadruple technology at different temperatures. 相似文献
The development of green, sustainable, and economical chemical processes represents the fundamental challenges in today's chemical field. In this context, light-driven organic synthesis using safe, abundant, and renewable light source can be considered an ideal procedure to reduce the thermochemical or electrochemical activation energy. Although various catalysts are used in light-driven organic conversion, the heavy metal toxicity and photocorrosion effect hinder their practical applications. Of the extensive photoactive materials, perovskite-based photocatalysts have fortified their applications in the field of photocatalytic organic reactions because of their unique nature including strong and wide light absorption, long excited state lifetimes, high photoluminescence quantum yield, efficient separation, and transport of photogenerated charge carriers. This review focuses on the recent progress in syntheses and applications of perovskite-based exceptional photocatalysts for organic reactions.
The first oxidative cross-coupling of allylsilanes with aryl boronic acids has been developed by palladium catalysis. The reaction between β-substituted allyl(trimethyl)silanes and a wide range of aryl boronic acids afforded allylarenes in moderate to good yields and excellent selectivity. On the basis of experimental results and literature reports, it was suggested that the reaction might start from transmetalation of aryl boronic acid with AgOAc followed by transmetalation with Pd(II) to give an arylpalladium acetate complex as a key intermediate. This intermediate underwent either electrophilic addition/desilylation or transmetalation with allylsilane and subsequent reductive elimination to give the final product. 相似文献
A ligand-free Pd-catalyzed cross-coupling of substituted allyl(trimethyl)silanes with aryl iodides enabled by silver salts was developed. This reaction delivered allylic arenes chemoselectively and regioselectively. The study suggested that the reaction might proceed through oxidative addition of ArI to Pd(0) followed by halide abstraction to give an electrophilic complex ArPdX, which further reacted with allyl(trimethyl)silanes via electrophilic addition/desilylation/reductive elimination to afford the allyl-aryl coupling products. 相似文献
The Ramanujan Journal - The alternating descent statistic on permutations was introduced by Chebikin as a variant of the descent statistic. We show that the alternating descent polynomials on... 相似文献
Journal of Mathematical Chemistry - The Harary index of a connected (molecular) graph is defined as the sum of reciprocals of distances between all its pairs of vertices. In this paper, we... 相似文献
We report herein a synthesis of 5,6-diarylbenzo[a]carbazoles by a sequence of 6π-electrocyclization followed by β-elimination. The highly functionalized 2,3-disubstituted indoles used for this cycloaromatization process are prepared by Pd-catalyzed cyclizative cross-coupling of ortho-alkynylanilines with ortho-alkynylbenzamides. The combination of these two reactions allows us to develop a facile synthesis of benzo[a]carbazoles directly from two easily accessible internal alkynes without isolation of the indole intermediates. 相似文献
