A series of RuII(1), RhIII(2), IrIII(3, 4), IrI(5) and PdII(6-9) complexes of the ‘instant carbene’ Nitron were prepared and characterized by 1H- and 13C-NMR, FT-IR and elemental analysis. The molecular...

A series of piano‐stool Ru (II) complexes (Ru1–7) bearing ethylenediamine with aryl and aliphatic groups were prepared and fully characterized by 1H, 13C, 19F and 31P NMR spectroscopy, FT‐IR and elemental analysis. The crystal structures of Ru2–4 and Ru7 were determined by X‐ray crystallography. They were successfully applied to the alpha(α)‐alkylation of aliphatic and aromatic ketones with alcohols via the borrowing hydrogen strategy in mild reaction conditions within a short time. The catalytic system has a broad substrate scope, which allows the synthesis of alpha alkylated ketones with excellent yields. The electronic and steric effects of complexes on catalytic activity were analysed. The influence of the carbon chain length of the ligand on the alpha‐alkylation reaction of ketones was also investigated. The catalytic cycle was also examined by 1H‐NMR spectroscopy in d8‐toluene.

A series of nitrile-modified N-heterocyclic carbene (NHC) complexes of Ir(III) (2a−e) and Ru(II) (3a−d) have been prepared by transmetallation of [IrCp*Cl 2 ] 2 and [RuCl 2 (pcymene)] 2 forming an in situ NHC−Ag complex. The structures of all complexes were characterized by 1 H NMR, 13 C NMR, and Fourier transform infrared (FT-IR) spectroscopies. And the structures were clearly elucidated by performing X-ray diffraction studies on 2b, 3a, and 3c single crystals. The complexes of NHC− Ir(III) (2a−e) and NHC−Ru(II) (3a−d) were investigated in the N-alkylation reaction of aniline derivatives with benzyl alcohols to form N-benzyl amines and in the N-methylation reaction of aniline derivatives with methanol. Both reactions were performed in solvent-free media. The Ir(III) complexes (2a−e) were found to perform essentially better than similar Ru(II) complexes (3a−d) in the N-alkylation and N-methylation reactions. Among the Ir(III) complexes (2a−e), the best results were obtained with 2b. The catalytic mechanisms of both reactions were revealed by 1 H NMR study. Formation of Ir-hydride species was observed for both reactions. This new report provides useful information to evaluate the activity of complexes and the differences in sensitivity between the NHCs.

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In recent years, introducing electrospun airfilters to enhance the removal of PM2.5 and PM10–2.5 has received much interest. In this study, a novel poly-(vinyl) alcohol (PVA)/carbon nanoparticle (CNP)/tea leaf extract (TLE), functionalized nanofibrous air filter (FNA) was fabricated using an electrospinning method. Novelty of the unique work in the blending of CNP and TLE, first of its kind, for the preparation of FNA. Polysaccharide crosslinked FNA has a carbon complex with two monosaccharide units to produce the intrinsic properties of the PM2.5 and PM10–2.5 removal efficiency. The FNA had promising traits of UV protection. The prepared FNA was characterized using physicochemical, mechanical, antimicrobial activity, etc., in addition to its PM2.5 and PM10–2.5 removal efficiency. Pore size and distribution study using the capillary flow porometry method has proved the structure of FNA. FNA exhibited excellent low pressure drop (110 Pa), which are promising characteristics for air purification. FNA from PVA: CNP: TLE exhibited high PM2.5 and PM10–2.5 removal efficiencies of 99.25% and 99.29%, respectively. Hence, the study proved.

This paper reports a new, practical, and environmentally friendly catalytic system for reduction of the ketones to the related alcohols with efficient reaction performance in water. Catalysts were generated in situ from rhodium, ruthenium and iridium transition metal compounds with commercially available piperidines [Piperidine (L 1 ), 2-hydroxymethylpiperidine (L 2 ), 3-hydroxymethylpiperidine (L 3 ), 4-hydroxymethylpiperidine (L 4 ), 4-hydroxypiperidine (L 5 )] as bifunctional ligands. Catalyst generated from RuCl 2 (PPh 3 ) 3 and 4-hydroxymethyl piperidine have shown the best activity in aqueous media which gave a 100% product yield. RuCl 2 (PPh 3 ) 3 , has showed a better efficiency than [RuCl 2 (p-cymene)] 2 , IrCl(PPh 3 ) 3 , or RhCl(PPh 3 ) 3 in HCOOH-HCOONa buffer solution. This study was also investigated the relationship between the structure of hydroxymethyl piperidine ligands and the catalytic activity.[a] Dr.

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