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The blue shift observed for the S analogue results from a larger HOMO-LUMO gap in the case of dithiolate ligands.In recent years, bioanalytical surface-enhanced Raman spectroscopy (SERS) has blossomed into a fast-growing research area. Owing to its high sensitivity and outstanding multiplexing ability, SERS is an effective analytical technique that has excellent potential in bioanalysis and diagnosis, as demonstrated by its increasing applications in vivo. SERS allows the rapid detection of molecular species based on direct and indirect strategies. Because it benefits from the tunable surface properties of nanostructures, it finds a broad range of applications with clinical relevance, such as biological sensing, drug delivery and live cell imaging assays. Of particular interest are early-stage-cancer detection and the fast detection of pathogens. Here, we present a comprehensive survey of SERS-based assays, from basic considerations to bioanalytical applications. Our main focus is on SERS-based pathogen detection methods as point-of-care solutions for early bacterial infection detection and chronic disease diagnosis. Additionally, various promising in vivo applications of SERS are surveyed. Furthermore, we provide a brief outlook of recent endeavours and we discuss future prospects and limitations for SERS, as a reliable approach for rapid and sensitive bioanalysis and diagnosis.A direct sp3 C-H amination of cyclic amines (dihydroquinoxalinones and dihydrobenzoxazinones) with dialkyl azo dicarboxylates accelerated by visible-light irradiation under metal and photocatalyst-free conditions is described. This protocol features very mild reaction conditions for the synthesis of aminal quinoxaline and benzoxazine derivatives with good to high yields (up to 99%). These aminal derivatives respresent versatile building blocks for the divergent synthesis of quinoxalin-2-one derivatives.Biomimetic superhydrophobic surfaces show great potential in oil-water separation, anti-icing and self-cleaning. However, due to the instability caused by its fragile structure and non-durable superhydrophobicity, it is difficult to apply them in the actual field. Here, by introducing surface wettability and analysing the mechanism of superhydrophobic failure, it is concluded that the reason for the failure of the superhydrophobic surface comes from the transition of the surface energy and the hysteresis of the contact angle (CA). On the basis of this analysis, it is concluded that the principle of designing a durable superhydrophobic surface is to satisfy one of the following three points improving the binding force between molecules, introducing durable materials and improving chemical durability. On this basis, a variety of preparation methods are proposed, such as assembly method and spray/dip coating method, and the design and preparation of a self-healing surface inspired by nature will also be included in the introduction. Last but not least, the preparation and application of a durable super-hydrophobic surface in oil-water separation, anti-icing and self-cleaning are also introduced in detail. This review reveals the conclusions and prospects of durable superhydrophobic surfaces, and aims to inspire more researchers to invest in this research.By combining NMR data (nuclear Overhauser effect and pseudocontact shifts) with luminescence measurements, we uncover how the structure of an anionic europium complex adapts to different solvent polarities as a result of the different relative proximities of the ion pairs. Epacadostat manufacturer In nonpolar solvents, the detected contact ion pairs, CIPs, indicate that the ions remain in proximity, with the molecular cation, and then perturbing and distorting the coordination polyhedron of the anion complex to a low symmetry configuration, which promotes luminescence. Differently, solvent separated ion pairs occur in polar solvents, indicating that the molecular ions have been disconnected. Thus, in polar solvents, the europium complex anion becomes free from the close influence of the molecular cation, allowing the coordination polyhedron to increase its symmetry, which in turn reduces the luminescence of the anionic europium complex. This reduction of coordination polyhedron symmetry by the close proximity of the molecular cation in nonpolar solvents was confirmed by additional photophysical measurements combined with quantum chemical RM1 calculations, suggesting that, in nonpolar solvents, the symmetry point group of the coordination polyhedron is C1, whereas in polar solvents it is either D2d or S4. The nonpolar solvents used were benzene, chloroform and dichloromethane; and the polar ones were acetone and acetonitrile. The synthesized ionic liquids were tetrakis [C5mim][La(BTFA)4] and [C5mim][Eu(BTFA)4], where BTFA stands for 4,4,4-trifluoro-1-phenyl-1,3-butanedione, lanthanoids (La3+ and Eu3+) and C5mim stands for 1-methyl-3-isopentylimidazolium. They were synthesized by a microwave methodology that is both fast and green (the synthetic reaction takes about 15 min) and also leads to more easily purifiable crystals.Tertiary benzylic alcohols react with oxoammonium salts, undergoing a tandem elimination/allylic oxidation to provide an allylic ether product in a single step. This mode of reactivity provides a rapid entry into allylic ethers from certain benzylic tertiary alcohols. The allylic ether may be cleaved under reductive conditions to reveal the allylic alcohol.An efficient indium-mediated cascade annulation reaction of 2-azidoaryl aldehydes with propargyl bromides is reported. The aromatic 5/6/6-fused heterocycles, [1,2,3]triazolo[1,5-a]quinoline derivatives, could be constructed in one pot in moderate yields with a broad substrate scope. Mechanistic studies indicated that the reaction proceeded through allenol formation, azide-allene [3 + 2] cycloaddition, and dehydration. The synthetic potential of the products including the denitrogenative functionalization and the Pd-catalyzed coupling reactions has also been explored.Facile synthesis of 4-allyl-/4-allenyl-4-(arylthio)-1,4-dihydroisoquinolin-3-ones via the visible-light-induced Doyle-Kirmse reaction of 4-diazo-1,4-dihydroisoquinolin-3-ones with allyl-/propargyl sulfides is reported. The reaction proceeds via the generation of free carbenes from cyclic diazo compounds followed by in situ formation of sulfonium ylide intermediates, which subsequently undergo [2,3-sigmatropic rearrangement] to give highly functionalized dihydroisoquinolinones in moderate to good yields. Broad substrate scope, and catalyst-free and mild conditions are the merits of this reaction.