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Heterocyclic and fused heterocyclic compounds are ubiquitously found in natural products and biologically interesting molecules, and many currently marketed drugs hold heterocycles as their core structure. In this chapter, recent advances on Pd-catalyzed synthesis of heterocycles in ionic liquids (ILs) are reviewed. In palladium catalysis, ILs with different cations and anions are investigated as an alternative recyclable and environmentally benign reaction medium, and a variety of heterocyclic compounds including cyclic ketals, quinolones, quinolinones, isoindolinones, and lactones are conveniently constructed. Compared to the traditional methods, these new approaches have many advantages, such as environmentally friendly synthetic procedure, easy product and catalyst separation, recyclable medium, which make them have the potential applications in industry.

The replacement of the H atom at the R−H⋯Nu synthon with a Group 14 element leads to a tetrel bond (TtB), which is a weak interaction between the electron density deficient side (the so-called σ or π hole) of a covalently bonded tetrel atom (Tt = C, Si, Ge, Sn or Pb) and a nucleophilic (Nu) region in the same (intramolecular) or another (intermolecular) molecular entity: R−Tt⋯Nu [R = Tt, Pn (pnictogen), Ch (chalcogen), metal, etc.; Nu = lone pair possessing Ha (halogen), Ch, Pn or metal atom, anion, π-system, radical, etc.]. Similarly to the hydrogen, halogen, chalcogen and pnictogen bonds as well as to π-interactions, the TtB is also of utmost importance for the development of new metal-complex catalysts, sensors, molecular switches, etc. For example, the activity and selectivity of enzymes or synthetic catalysts can be highly affected by the action of the secondary coordination sphere of a metal complex in reactions involving the carbon atom of a TtB. In this chapter, we discuss a few examples, taken from the Cambridge Structural Database, in which TtB aggregates tectons into high-dimensional supramolecular architectures.

The one-pot synthesis of copper, cesium-containing ordered mesoporous alumina via self-assembly of a copper precursor and aluminumisopropoxide in the presence of a triblock copolymer (as a structure directing agent) was investigated. The resulting copper, cesium-containing mesoporous alumina possessed relatively high BET surface area, well-developed mesoporosity, and a larger pore width. In comparison to pure alumina, copper, cesium-containing alumina samples exhibited higher BET surface area, larger mesopores, improved thermal stability and a larger quantity of acid sites. Also, long range ordering of the aforementioned samples was observed for cesium molar percentages as high as 20%. The generality of the strategy used for the synthesis of copper contained alumina was demonstrated by preparation of other metal containing alumina oxides. This method represents an important step towards the facile and reproducible synthesis of ordered mesoporous alumina which contains other elements for various applications where large and accessible pores with high loading of catalytically active metal oxides are needed.

Amine modified carbon quantum dots was synthesized by the acid oxidation method and hydrothermal route from coal in Barkol coalmine area and amine water. The features and properties of the product were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Photoluminescence Spectra (PL), UV-visible Spectroscopy (UV/vis), Transmission Electron Microscopy (TEM) and X-ray diffraction (XRD). The results indicated that the GQDs have bright aquamarine with high water solubility, good photostability.

The carbothermal reduction and nitridation has been used to synthesize composite ceramic powders from rice husk ash (RHA) with alumina addition of 0.02, 0.1, 0.5 and 1 (Al₂O₃/SiO₂) respectively. The phase composition of products after calcining at high temperatures was almost sensitive to the Al₂O₃ content. The sequence of phase-formation except for SiC and Si₃N₄ with alumina addition was followed by Si₂N₂O→Si_1.62Al_0.38 N_1.62O_1.38→Si₃Al₃O₃N₅ for 1500 °C, and Si₃Al₃O₃N₅→AlN for 1550 °C. The results highlighted that effects of alumina impurity on the synthesis of composite ceramic powders from rich husk ash were significant.

The quasi-one-step method was used to synthesize hyperbranched polyesteramide by using diethanolamine and butanedioic anhydride as raw materials. Fourier transform infrared spectrometer (FTIR), Ubbelohde viscometer and DSC-TGA were used to identify the structure, viscosity and thermal stability of hyperbranched polyesteramide, respectively. In this investigation, the dependence of viscosity on hyperbranched polyesteramide in the presence of end-capped reagents was studied. Benzoic acid, stearic acid, crylic acid, α-methyl crylic acid and cinnamic acid as end-capped reagents can reduce the viscosity. The logarithmic value of viscosity with end-capped reagents (0.019-0.057dL/g) was much lower than the viscosity (0.146 dL/g) without end-capping reagent. In thermal analysis, T_d (thermal decomposition temperature) of hyperbranched polyesteramide was at the temperature of 316.3 °C, Tg (Glass transition temperature) was at the temperature of 270 °C. The results showed that the product exhibits low logarithmic viscosity value, good solution and relative thermal stability, which has a potential application values in rheology modifier of macromolecular materials.