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In this work, polyaniline-cellulose nanofiber (PANI-CNF) nanocomposites were prepared by in-situ polymerization of aniline on 2,2,6,6-tetramethyl1-piperidinyloxy (TEMPO) oxidized CNFs. Fourier transform infrared spectroscopy and transmission electron microscope demonstrate the successful polymerization of aniline on CNFs. The PANI-CNF nanocomposites were added as nanofillers to waterborne epoxy resin (WER) in different proportions. The composite coatings with different contents of PANI-CNFs were prepared by fabricating the mixture on the Q235 steel sheets. The corrosion resistance of different coatings was evaluated by potentiodynamic polarization and electrochemical impedance spectroscopy. The results confirmed that composite coatings containing 0.5% PANI-CNF exhibit the optimum anticorrosion behaviors and best corrosion resistance, which shows the lowest corrosion current density (1.788 * [10.sup.-7] A/[cm.sup.-2]) and highest corrosion potential (-0.458 V). In addition, PANI-CNF can significantly enhance the anticorrosion performance of WER coatings and maintain a high value even after 40 days of immersion in NaCl solutions. The above performances are attributed to the synergistic effect of the barrier effects and the passivation mechanism. Therefore, the bio-based composite materials developed in this work are promising in enhancing the corrosion protection of mild steel, which is essential for the sustainable development of waterborne coatings. KEYWORDS anticorrosive coating, cellulose nanofiber, nanocomposite, polyaniline, waterborne epoxy resin, 1 | INTRODUCTION Metals are very important and the most used materials in modern life and industry due to their competitive prices, good mechanical performances, and high recyclability. However, most [...]

Abstract An extensive medicinal chemistry campaign and subsequent SAR studies led to the discovery of the highly potent and selective JAK1/3 inhibitor R545. To support advanced pre-clinical DMPK studies of R545 , the isotopically labeled versions of the drug and its metabolite R935 were required. Herein, we describe the development of synthetic routes to deuterium-labeled [ D 7 ] -R545 and its oxidative metabolite [ D 7 ] -R935. Deuterium atoms were introduced at several sites in the target molecules by employing a convergent synthesis strategy. The desired regiochemistry at the right-hand side of [ D 7 ] -R935 was established via a newly discovered protecting group-directed bromination. The described synthetic approach gave rise to the desired deuterium-labeled target compounds and sufficient quantities were synthesized to enable pre-clinical DMPK studies. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

It is suggested, that a DMSO radical generated in tBuOK/DMSO systems works as the crucial initiator for the title cyclization process. [ABSTRACT FROM AUTHOR]

A novel zinc(II) metal-organic framework (MOF) {[(CH 3 ) 2 NH 2 ] 2 [Zn 5 (TDA) 4 (TZ) 4 ] . 4DMF} n ( 1 ) (H 2 TDA = thiophene-2,5-dicarboxylic acid and HTZ = 1 H -1,2,4-Triazole) based on Zn 5 (COO) 2 (TZ) 4 pentametallic clusters and thiophene-2,5-dicarboxylic acid was synthesized and structurally characterized via the mixed-ligand strategy. This MOF exhibits a uninodal 6-connected anionic framework with pcu topology and shows solvent stability. Post-functionalization via cation exchange of 1 with Eu 3+ and Tb 3+ afforded two lanthanide (III) functionalized MOFs: Eu 3+ @1 and Tb 3+ @1 . 1 as well as Eu 3+ @1 and Tb 3+ @1 were utilized as a highly selective and sensitive turn-off luminescent sensors for detecting aniline, benzaldehyde in DMF and Cr 2 O 7 2− , CrO 4 2− in water with low detection limits. More importantly, it is rather rare in MOF-based luminescent probes that 1 and its lanthanide (III) post-functionalized materials ( Eu 3+ @1 and Tb 3+ @1 ) can detect aniline, benzaldehyde, Cr 2 O 7 2− and CrO 4 2− . Furthermore, the sensitivity of 1 as luminescent probes for detecting aniline and benzaldehyde could be improved via post-functionalization with Eu 3+ ions. [ABSTRACT FROM AUTHOR]

An intramolecular coupling of tertiary amines and anilines is developed starting from 2-(N,N-dialkylamino)anilines. [ABSTRACT FROM AUTHOR]