Copper-Phosphido Catalysis: Enantioselective Addition of Phosphines to Cyclopropenes**

We describe a copper catalyst that promotes the addition of phosphines to cyclopropenes at ambient temperature. A range of cyclopropylphosphines bearing different steric and electronic properties can now be accessed in high yields and enantioselectivities. Enrichment of phosphorus stereocenters is also demonstrated via a Dynamic Kinetic Asymmetric Transformation (DyKAT) process. A combined experimental and theoretical mechanistic study supports an elementary step featuring insertion of a Cu^I-phosphido into a carbon-carbon double bond. Density functional theory calculations reveal migratory insertion as the rate- and stereo-determining step, followed by a syn-protodemetalation.     

Photosynthesis-Mediated Intracellular Biomineralization of Gold Nanoparticles inside Chlorella Cells towards Hydrogen Boosting under Green Light

Engineering living microorganisms to enhance green biomanufacturing for the development of sustainable and carbon-neutral energy strategies has attracted the interest of researchers from a wide range of scientific communities. In this study, we develop a method to achieve photosynthesis-mediated biomineralization of gold nanoparticles (AuNPs) inside Chlorella cells, where the photosynthesis-dominated reduction of Au³⁺ to Au⁰ allows the formed AuNPs to locate preferentially around the thylakoid membrane domain. In particular, we reveal that the electrons generated by the localized surface plasmon resonance of AuNPs could greatly augment hypoxic photosynthesis, which then promotes the generation and transferring of photoelectrons throughout the photosynthetic chain for augmented hydrogen production under sunlight. We demonstrate that the electrons from AuNPs could be directly transferred to hydrogenase, giving rise to an 8.3-fold enhancement of Chlorella cells hydrogen production independent of the cellular photosynthetic process under monochromatic 560 nm light irradiation. Overall, the photosynthesis-mediated intracellular biomineralization of AuNPs could contribute to a novel paradigm for functionalizing Chlorella cells to augment biomanufacturing.     

Nitrene-Mediated Enantioselective Intramolecular Olefin Oxyamination to Access Chiral γ-Aminomethyl-γ-Lactones

Attaching a nitrene precursor to an intramolecular nucleophile allows for a catalytic asymmetric intramolecular oxyamination of alkenes in which the nucleophile adds in an endocyclic position and the amine in an exocyclic fashion. Using chiral-at-ruthenium catalysts, chiral γ-aminomethyl-γ-lactones containing a quaternary carbon in γ-position are provided in high yields (up to 99 %) and with excellent enantioselectivities (up to 99 % ee). DFT calculations support the possibility of both a singlet (concerted oxyamination of the alkene) and triplet pathway (stepwise oxyamination) for the formation of the predominant stereoisomer. γ-Aminomethyl-γ-lactones are versatile chiral building blocks and can be converted to other heterocycles such as δ-lactams, 2-oxazolidinones, and tetrahydrofurans.     

Quality control and original discrimination of Ganoderma lucidum based on high-performance liquid chromatographic fingerprints and combined chemometrics methods

In this paper, the feasibility and advantages of employing high-performance liquid chromatographic (HPLC) fingerprints combined with chemometrics methods for quality control of the cultured fruiting bodies of Ganoderma lucidum were investigated and demonstrated for the first time. In order to compare the HPLC fingerprints chromatograms between G. lucidum from different origins, the similarities of all the 60 samples and relative peak areas of 19 characteristic compounds were firstly calculated respectively. Then different pattern recognition procedures, including hierarchical cluster analysis (HCA), principal component analysis (PCA), partial least squares-discrimination analysis (PLS-DA) and soft independent modeling of class analogy (SIMCA) were applied to classify the G. lucidum samples according to their cultivated origins. Consistent results were obtained to show that G. lucidum samples could be successfully grouped in accordance with the province of origin. Furthermore, four marker constituents were screened out to be the most discriminant variables, which could be applied to accurate discrimination and quality control of G. lucidum by quantitative analysis. Finally, the chemical properties of those samples were also investigated to find out the differences of quality between them. Ranked in decreasing order, the quality of the G. lucidum can be arranged as Jinzhai/Huangshan, Shandong followed by Zhejiang samples. Our results revealed that the developed method has potential perspective for the original discrimination and quality control of G. lucidum.     

Food Waste Fermentation to Fumaric Acid by <Emphasis Type="Italic">Rhizopus arrhizus RH7-13</Emphasis>

Fumaric acid as a four-carbon unsaturated dicarboxylic acid is widely used in the food and chemical industries. Food waste (FW), rich in carbohydrates and protein, is a promising potential feedstock for renewable bio-based chemicals. In this research, we investigated the capability of Rhizopus arrhizus RH7-13 in producing fumaric acid from FW. The liquid fraction of the FW (L-FW) was proven to be the best seed culture medium in our research. When it was however used to be fermentation medium, the yield of fumaric acid reached 32.68 g/L, at a volumetric production of 0.34 g/L h. The solid fraction of FW mixed with water (S-FW) could also be used as fermentation medium when a certain amount of glucose was added, and the yield of fumaric acid reached 31.26 g/L. The results indicated that both fractions of FW could be well utilized in fermentation process and it could replace a part of common carbon, nitrogen, and nutrient. The process has an application potential since reducing the costs of raw materials.     

Improving surface quality of polyethylene terephthalate film for large area flexible electronic applications

Lamination is a method utilized to protect flexible electroluminescence device against environmental hazards, such as dust, moisture, and water vapor. The materials are typically joined together using adhesive or cohesion of the materials during the lamination process. Polyethylene terephthalate (PET) is commonly used as the substrate film where electroluminescence patterns are printed. However, PET film has a relatively low surface energy and high contact angle, which would cause relatively weak laminating strength. This paper discusses the use of atmospheric plasma as a surface treatment method to modify PET and laminating films’ interface to improve bonding and laminating quality. Experimental results revealed that atmospheric plasma process reduced the contact angle of both PET and laminating films. Functional groups favoring hydrophilicity were found on the films’ interface after the atmospheric plasma treatment. These effects consequently increased surface energies of both films and favored bonding between the films. The treated films thus had increased laminating strength by approximately six times without compromising the transparency quality.     

A one-component photoinitiator based on 4-methylbenzophenone and morpholine

4-Benzoylbenzyl-3-morpholinopropanoate was synthesized, characterized and used as a one-component photoinitiator of Type II. Real-time near-IR spectroscopy was used to study the kinetics of conversion of double bonds of monomers vs. irradiation time. In this initiator, the radicals could be generated through hydrogen abstraction based on intermolecular reaction. Light intensity, concentration of initiator, and the functionality of acrylates affected the polymerization rate and the final monomer conversion.     

Lipid profiling of cyanobacteria Synechococcus sp. PCC 7002 using two‐dimensional liquid chromatography with quadrupole time‐of‐flight mass spectrometry

Glycerolipid is a main component of membranes in oxygenic photosynthetic organisms. Up to now, the majority of publication in this area has focused on the physiological functions of glycerolipids and lipoprotein complexes in photosynthesis, but the study on the separation and identification of glycerolipids in thylakoid membrane in cyanobacteria is relatively rare. Here we report a new method to separate and identify five photosynthetic glycerolipid classes, including monoglucosyl diacylglycerol, monogalactosyl diacylglycerol, digalactosyl diacylglycerol, sulfoquinovosyl diacylglycerol, and phosphatidylglycerol, in cyanobacteria Synechococcus sp. PCC 7002 by two‐dimensional (normal‐ and reversed‐phase) liquid chromatography online coupled to quadrupole time‐of‐flight mass spectrometry. Over twice as many lipid species were detected by our method compared to the previously reported methods. Ten new odd‐chain fatty acid glycerolipids were discovered for the first time. Moreover, complete separation of isomers of monogalactosyl diacylglycerol and monoglucosyl diacylglycerol was achieved. According to the tandem mass spectrometry results, we found that the head group of monoglucosyl diacylglycerols was not as stable as that of monogalactosyl diacylglycerols, which might explain why the organism chose monogalactosyl diacylglycerols and digalactosyl diacylglycerols instead of monoglucosyl diacylglycerols as the main content of the photosynthetic membranes in the history of evolution. This work will benefit further research on the physiological function of glycerolipids.     

Theoretical studies on the complexation of Eu(III) and Am(III) with HDEHP: structure,bonding nature and stability

Separation of trivalent lanthanides (Ln(III)) and actinides (An(III)) is a key issue in the advanced spent nuclear fuel reprocessing. In the well-known trivalent actinide lanthanide separation by phosphorus reagent extraction from aqueous komplexes (TALSPEAK) process, the organophosphorus ligand HDEHP (di-(2-ethylhexyl) phosphoric acid) has been used as an efficient reagent for the partitioning of Ln(III) from An(III) with the combination of a holdback reagent in aqueous lactate buffer solution. In this work, the structural and electronic properties of Eu³⁺ and Am³⁺ complexes with HDEHP in nitric acid solution have been systematically explored by using scalar-relativistic density functional theory (DFT). It was found that HDEHP can coordinate with M(III) (M=Eu, Am) cations in the form of hydrogen-bonded dimers HL₂^- (L=DEHP), and the metal ions prefer to coordinate with the phosphoryl oxygen atom of the ligand. For all the extraction complexes, the metal-ligand bonds are mainly ionic in nature. Although Eu(III) complexes have higher interaction energies, the HL₂^- dimer shows comparable affinity for Eu(III) and Am(III) according to thermodynamic analysis, which may be attributed to the higher stabilities of Eu(III) nonahydrate. It is expected that this work could provide insightful information on the complexation of An(III) and Ln(III) with HDEHP at the molecular level.