Towards an efficient, mild and sustainable approach for nitroarene hydrogenation by Pd nanoparticles in aqueous medium.

Novel bio-nanohybrids based on room temperature one-pot synthesized lipase-nanoparticle systems were developed and characterized in this work, with subsequent investigations on their catalytic activities and stability as compared to the free enzymes. Preliminary results pointed to excelling stabilities, solvent tolerance, and activities as compared to free lipases, opening up further scenarios for their utilization under continuous flow conditions as well as in tandem reactions.

The market for products based on nanotechnology increases day by day, and with it the use of nanomaterials and the generation of waste that contain nanowaste. Among the vast variety of nanomaterials available, gold nanoparticles (AuNPs) are within the most studied and applied ones in commercial products. This current situation requires both, the development of recovery methods to reduce the amount of produced nanowaste and new synthetic methods that allow the reuse of recovered gold for new nanomaterial production; in both cases keeping in mind economical and ecological reasons. In this work, a methodology to recover gold from aqueous laboratory nanowaste and to transform it into an aqueous HAuCl 4 solution was developed, using extremely simple procedures and easily available chemical reagents (NaCl, HCl, H 2 O 2), allowing the recovery of more than 99% of the original gold. The experiments were performed using both simulated and real laboratory nanowastes obtaining practically the same results. Moreover, the subsequent use of the obtained aqueous HAuCl 4 solution, from the recovered gold, to produce spherical AuNPs through a seed-mediated approach was demonstrated. Thus, this work presents, for the first time to the best of our knowledge, a complete recycling cycle from nanowaste, to the reagent and back to the nanomaterial.

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Light signals trigger precise changes in gene expression networks that activate distinctive developmental programs in plants. The transcriptome is shaped at different stages, both by the regulation of gene expression and also by posttranscriptional mechanisms that alter the sequence or abundance of the transcripts generated. Posttranscriptional mechanisms have attracted much interest in recent years with the advent of high‐throughput technologies and bioinformatics tools. One such posttranscriptional process, alternative splicing, increases proteome diversity without increasing gene number by changing the function of individual proteins, while another, miRNA‐mediated gene silencing, fine‐tunes the amount of mRNA produced. The manner in which plants make use of these two crucial posttranscriptional mechanisms to respond to light and adapt to their environment is the focus of active research. In this review, we summarize the current knowledge of light‐mediated posttranscriptional control in Arabidopsis thaliana and focus on the biological impact of the various posttranscriptional processes. We also discuss a potential cross talk between the alternative splicing and miRNA pathways, highlighting the complexity of light responsiveness.

The synthesis of 3-benzazepin-2-ones using commercially available 2-(2-iodophenyl)acetic acid as starting material is described. The synthetic strategy involves the S RN 1 substitution reaction in DMSO as solvent under photoinitiation, using ketone enolate ions as nucleophiles to obtain ε-oxo acids, followed by a condensation reaction of ε-oxo acids with ammonium acetate in glacial acetic acid to produce novel 3-benzazepin-2-ones. The target compounds are afforded in regular to good yields and the factors governing the distribution of substitution products are discussed.

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Aqueous Mizoroki–Heck coupling reactions under microwave irradiation (MW) were carried out with a colloidal Pd nanocatalyst stabilized with poly(N-vinylpyrrolidone) (PVP). Many stilbenes and novel heterostilbenes were achieved in good to excellent yields starting from aryl bromides and different olefins. The reaction was carried out in a short reaction time and with low catalyst loading, leading to high turnover frequency (TOFs of the order of 100 h−1). The advantages like operational simplicity, high robustness, efficiency and turnover frequency, the utilization of aqueous media and simple product work-up make this protocol a great option for stilbene syntheses by Mizoroki–Heck reaction.