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In a flash: Pyrotechnic incendiary formulations with good stabilities toward various ignition stimuli have been developed without the need for barium or perchlorate oxidizers. KIO4 and NaIO4 were introduced as pyrotechnic oxidizers and exhibited excellent pyrotechnic performance. The periodate salts may garner widespread use in military and civilian fireworks because of their low hygroscopicities and high chemical reactivities.

Synthesis, structure, and olefin metathesis activity of a surface complex [(≡Si-O-)W(═O)(CH)-ImN] (4) (Im = 1,3-bis(2,6-diisopropylphenyl)imidazolin-2-iminato) supported on silica by a surface organometallic chemistry (SOMC) approach are reported. The reaction of N-silylated 2-iminoimidazoline with tungsten(VI) oxytetrachloride generated the tungsten oxo imidazolin-2-iminato chloride complex [ImNW(═O)Cl] (2). This was grafted on partially dehydroxylated silica pretreated at 700 °C (SiO) to afford a well-defined monopodal surface complex [(≡Si-O-)W(═O)Cl-ImN] (3). 3 underwent alkylation by ZnMe to produce [(≡Si-O-)W(═O)(CH)-ImN] (4). The alkylated surface complex was thoroughly characterized by solid-state NMR, elemental microanalysis, Raman, FT-IR spectroscopies, and XAS analysis. 4 proved to be an active precatalyst for self-metathesis of terminal olefins such as propylene and 1-hexene.

An efficient palladium catalyst supported on fibrous silica nanospheres (KCC‐1) has been developed for the hydrogenation of alkenes and α,β‐unsaturated carbonyl compounds, providing excellent yields of the corresponding products with remarkable chemoselectivity. Comparison (high‐resolution TEM, chemisorption) with analogous mesoporous (MCM‐41, SBA‐15) silica‐supported Pd nanocatalysts prepared under identical conditions, demonstrates the advantage of employing the fibrous KCC‐1 morphology versus traditional supports because it ensures superior accessibility of the catalytically active cores along with excellent Pd dispersion at high metal loading. This morphology ultimately leads to higher catalytic activity for the KCC‐1‐supported nanoparticles. The protocol developed for hydrogenation is advantageous and environmentally benign owing to the use of HCOOH as a source of hydrogen, water as a solvent, and because of efficient catalyst recyclability and durability. The recycled catalyst has been analyzed by XPS spectroscopy and TEM showing only minor changes in the oxidation state of Pd and in the morphology after the reaction, thus confirming the robustness of the catalyst.

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The film prepared using a blend of hydroxypropyl methyl cellulose (HPMC) and polyvinyl alcohol (PVA) was investigated for immobilization of Rhizopus oryzae lipase. These immobilized lipase films were characterized using a combination of techniques like SEM, TGA, FT-IR, and Karl Fischer titration analysis. The biocatalyst was subjected to transesterification reaction of benzyl alcohol with vinyl acetate and was optimized for various reaction parameters such as effect of support, molar ratio, solvent, concentration of biocatalyst, time and temperature. Furthermore, the developed methodology was then effectively applied to various alcohols for synthesis of industrially important acetates providing good to excellent yields of desired products. Interestingly, the experimental results demonstrated catalytic activity of immobilized lipase to be 4-fold greater than that of free lipase for transesterification reaction. The immobilized biocatalyst was effectively recycled for four consecutive cycles and exhibited remarkable stability for a period 90 days.

Gold nanoparticles (Au NPs) of different sizes were supported on fibrous silica nanospheres (KCC‐1) by various methods. The size and the location of the Au NPs on the support were found to depend on the preparation method. The KCC‐1‐supported Au NPs were thoroughly characterized by using HR‐TEM, XRD, X‐ray photoelectron spectroscopy, UV, and Brunauer–Emmett–Teller surface area measurements and were applied in catalysis for the oxidation of CO. The catalytic performance is discussed in relation to the morphological properties of KCC‐1.

A well-defined silica-supported monoalkylated tungsten dioxo complex [(Si–O−)­W­(O)2(CH2– t Bu)] was prepared by treatment of highly dehydroxylated silica (SiO2‑700: silica treated at 700 °C under high vacuum) with an ionic precursor complex [NEt4]­[W­(O)3(CH2– t Bu)]. The identity of the resulting neutral monoalkylated tungsten dioxo surface complex was established by means of elemental microanalysis and spectroscopic studies (IR, solid-state NMR, Raman, and X-ray absorption spectroscopies). The supported tungsten complex was found to act as a precatalyst for the self-metathesis of 1-octene in a batch reactor. The mechanistic implications of this reaction are discussed with the support of DFT calculations highlighting the potential occurrence of thus-far unexplored mechanistic pathways.