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Visible light-induced, transition metal-free oxidative dehydroxylation and C–H amidation of α-hydroxy ketones involving Ritter-type amidation has been developed, leading to the selective synthesis of α,α-diamido- and α-monoamido ketones with tunable selectivity as well as broad substrate tolerance. [ABSTRACT FROM AUTHOR]

Visible‐light photocatalysis is a rapidly developing and powerful strategy to initiate organic transformations, as it closely adheres to the tenants of green and sustainable chemistry. Generally, most visible‐light‐induced photochemical reactions occur through single‐electron transfer (SET) pathways. Recently, visible‐light‐induced energy‐transfer (EnT) reactions have received considerable attentions from the synthetic community as this strategy provides a distinct reaction pathway, and remarkable achievements have been made in this field. In this Review, we highlight the most recent advances in visible‐light‐induced EnT reactions. Making light of synthesis: The distinctive reaction pathways provided by visible‐light‐induced energy transfer (EnT) has resulted in it receiving considerable attention. This Review discusses the most recent advances in visible‐light‐induced EnT reactions. [ABSTRACT FROM AUTHOR]

Photokatalyse mit sichtbarem Licht ist eine sich schnell entwickelnde und wirksame Strategie zur Initiierung organischer Umwandlungen, und sie folgt den Prinzipien einer grünen und nachhaltigen Chemie. Im Allgemeinen verlaufen die Reaktionspfade der meisten durch sichtbares Licht induzierten photokatalytischen Reaktionen über einen Einelektronentransfer (single‐electron transfer, SET). Neuerdings erfahren auch Energietransferreaktionen (EnT‐Reaktionen), welche durch sichtbares Licht induziert werden, beträchtliche Aufmerksamkeit, da diese Strategie einen spezifischen Reaktionsweg aufweist und bemerkenswerte Fortschritte in diesem Feld erzielt wurden. In diesem Aufsatz diskutieren wir die neuesten Fortschritte im Bereich der durch sichtbares Licht induzierten EnT‐Reaktionen. Sichtbare Photokatalyse: Durch sichtbares Licht induzierte Energietransferreaktionen (EnTs) haben beträchtliche Aufmerksamkeit erfahren, da sie spezifische Reaktionsmechanismen aufweisen. In diesem Aufsatz werden die neuesten Fortschritte in diesem Gebiet diskutiert. [ABSTRACT FROM AUTHOR]

Furfural and 5-hydroxymethyl furfural (HMF) are abundantly available biomass-derived renewable chemical feedstocks, and their oxidation to furoic acid and furan-2,5-dicarboxylic acid (FDCA), respectively, is a research area with huge prospective applications in food, cosmetics, optics, and renewable polymer industries. Water-based oxidation of furfural/HMF is a lucrative approach for simultaneous generation of H 2 and furoic acid/FDCA. However, this process is currently limited to (photo)electrochemical methods that can be challenging to control, improve, and scale up. Herein, we report well-defined ruthenium pincer catalysts for direct homogeneous oxidation of furfural/HMF to furoic acid/FDCA, using alkaline water as the formal oxidant while producing pure H 2 as the reaction byproduct. Mechanistic studies indicate that the ruthenium complex not only catalyzes the aqueous oxidation but also actively suppresses background decomposition by facilitating initial Tishchenko coupling of substrates, which is crucial for reaction selectivity. With further improvement, this process can be used in scaled-up facilities for a simultaneous renewable building block and fuel production.

Glycolic acid is a useful and important α-hydroxy acid that has broad applications. Herein, the homogeneous ruthenium catalyzed reforming of aqueous ethylene glycol to generate glycolic acid as well as pure hydrogen gas, without concomitant CO 2 emission, is reported. This approach provides a clean and sustainable direction to glycolic acid and hydrogen, based on inexpensive, readily available, and renewable ethylene glycol using 0.5 mol % of catalyst. In-depth mechanistic experimental and computational studies highlight key aspects of the PNNH-ligand framework involved in this transformation., (© 2020 Wiley-VCH GmbH.)

Liquid organic hydrogen carriers (LOHCs) are powerful systems for the efficient unloading and loading molecular hydrogen. Herein, a liquid-to-liquid organic hydrogen carrier system based on reversible dehydrogenative coupling of ethylene glycol (EG) with ethanol catalysed by ruthenium pincer complexes is reported. Noticeable advantages of the current LOHC system is that both reactants (hydrogen-rich components) and the produced esters (hydrogen-lean components) are liquids at room temperature, and the dehydrogenation process can be performed under solvent and base-free conditions. Moreover, the hydrogenation reaction proceeds under low hydrogen pressure (5 bar), and the LOHC system has a relatively high theoretical gravimetric hydrogen storage capacity (HSC>5.0 wt %), presenting an attractive hydrogen storage system., (© 2020 Wiley‐VCH GmbH.)

Two visible-light driven alkenylation reactions of unactivated alkyl bromides, which were enabled by the use of Ir(dF(CF3)ppy)2(dtbbpy)PF6 as the photocatalyst and (TMS)3SiH as the atom transfer reagent to activate the alkyl bromides, were described for the first time. These protocols can be used to produce a variety of alkenes from easily available feedstock with good reaction efficiency and high chemoselectivity under mild reaction conditions. To further demonstrate the applicability of the present strategy, the alkenylation of bioactive molecules and glycosyl bromides, as well as the alkynylation of unactivated alkyl bromides, was proven to be feasible.

A novel visible-light-responsive chiral ligand has been developed by grafting a triplet state photosensitizer to chiral bisoxazoline ligands. Complexation of this ligand with Ni(acac) 2 results in a powerful catalyst for the asymmetric oxidation reaction of β-ketoesters, which uses oxygen or air as the green oxidant and visible light or sunlight as the ideal driving force. Using this protocol, products containing the α-hydroxy-β-dicarbonyl motif are produced in high yields and with excellent enantiopurities.

This study was aimed to explore the pathogenesis of type III familial hemophagocytic lymphohistiocytosis (FHL3) via susceptibility gene UNC13D involving in homologous recombination repair (HRR) of DNA double-strand break (DSB). By means of DNA homologous recombination repair, the change of homologous recombination repair rate of normal control cells and DR-U2OS cells after down-regulation of UNC13D was detected; the UNC13D gene related function was explored. The results showed that DR-U2OS cells displayed a significant reduction in homologous recombination repair of DNA DSB after siRNA knockdown of UNC13D, compared to its normal control cell counterparts (P < 0.05), suggesting that UNC13D was involved in DNA double-stranded breakage repair. It is concluded that UNC13D gene mutation may be involved in the pathogenesis of FHL3 via its dual effects of both the cytotoxic granule exocytosis and decrease of homologous recombination repair rate after the DNA double-strand break, therefore, providing a new theoretical basis to reveal the pathogenesis of FHL3.

Objective: To investigate the underlying tumor susceptibility mechanisms and reasons for the high risk of cancer in Fanconi anemia (FA)., Methods: Gene Set Enrichment Analysis (GSEA) was performed to compare gene expression profiles between 21 FA patients' bone marrow (BM) mononuclear cell (BMNC) and 11 normal controls in cancer related gene sets from NCBI GEO database, then core enriched genes were identified by further investigation. Through enrichment analyzing biological processes of gene ontology sets and structural genomic gene sets between FA expression profiles and control, more details related with its tumor susceptibility had been revealed., Results: Compared with normal control, gene expression in FA group had significant been enriched in resistance to Bcl-2 inhibitor gene set, fibroblast growth factors signalling pathways, insulin and insulin-like growth factors (IGF) signalling pathways induced cancer genesis gene sets. The high level of D4S234E, SST, FGFs, IGFs, FGFRs and IGFBP expression provided an initiate environment for tumorgenesis and drug resistance. There were significant differences in biogenesis extracellular molecules and cytomembrane structure organizations between FA and control. Genes with promoter regions around transcription start sites containing either motif RRCAGGTGNCV or CCTNTMAGA were enriched and those former genes match annotation for tumorgenic transcription factor 3 (TCF3)., Conclusions: The high tumor susceptibility of FA patients may be closely related with the dramatic changes in cancer related growth factors and hormones environment. This study provides new insights into tumor susceptibility mechanism in FA patients.