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Leoligin, a tetrahydrofuran lignan isolated from the root of the edelweiss plant, was synthesised from veratraldehyde (2 mol), diethyl succinate and 2-methyl-(Z)-2-butenoic acid. Initially, veratraldehyde and diethyl succinate underwent a Stobbe condensation to yield a C6-C5 acid which, after esterification, was condensed with a second molecule of veratraldehyde to generate a 2,3,4-trisubsituted γ-butyrolactone intermediate. Two reduction steps yielded a triol, which was ring-closed with tosyl chloride to form a hydroxymethyl-tetrahydrofuran, esterification of which with 2-methyl-(Z)-2-butenoic acid generated leoligin.

Electrochemical water splitting is considered to be a promising way to produce hydrogen in industry. Seeking for highly efficient electrocatalysts to boost the oxygen evolution reaction (OER) which is the pivotal step of electrocatalysis is significant and challenging. Herein, we report a facile method to synthesize bimetallic (Fe/Ni) nanoparticles embedded in nitrogen-doped carbon nanotube, which is derived from metal-organic frameworks (MOFs). The optimized catalyst FeNi@OCNT achieves a low overpotential of 289 ​mV at 10 ​mA ​cm−2 with a small Tafel slope of 40.8 ​mV dec−1 in 1 ​M KOH, and it exhibits long-term durability. Its excellent electrocatalytic performance can be attributed to the synergistic effect among the components, including bimetals, heteroatoms, carbon nanotubes and FeNi alloy nanoparticles. This work can provide a new idea in inspiring more strategies to synthesize high-performance and stable oxygen evolution reaction catalysts.

The first total synthesis of the dihydrobenzofuran neolignan quiquesetinerviusin A and its related structure have been described. Phenolic coupling is the key step to constructing the dihydrobenzofuran skeleton with vanillin as the raw material. The hydroxyl group was protected with dihydropyran (DHP) and the ester group was reduced with diisobutylaluminium hydride (DIBAL-H) in order to obtain the crucial intermediate diol, which was then condensed with an acid ligand to give the desired compounds following removal of the protecting groups.

The separation of gas molecules with similar diameters and shapes is an important area of research. Herein, we carefully studied a Ti-based metal-organic framework (NTU-9). The six coordination sites of each Ti4+ atom in this MOF are evenly distributed by three dobdc4- to form a two-dimensional (2-D) layered structure. Uncoordinated carboxyl O atoms between layers create a robust 3D framework by forming hydrogen bonds. The Brunauer-Emmett-Teller (BET) surface area of NTU-9 at 77 K is 917 m2 g−1. Benefit from the polar oxygen atoms vast in the surface of the one-dimensional (1-D) channel, NTU-9 shows a C2H2 adsorption capacity of 118 cm3 g−1 and a C2H2/CO2 selectivity of 3.5 under ambient conditions and has a moderate heat of adsorption for C2H2 (30 kJ mol−1). These findings may provide alternative strategies for gas separation.

The design and synthesis of efficient electrocatalysts are important for electrochemical conversion technologies. The oxygen evolution reaction (OER) is a key process in such conversions, having applications in water splitting and metal–air batteries. Here, bimetallic carbon nanocubes electrocatalysts are derived from Hofmann-type metal–organic frameworks by carbonization and oxidization (FeNi@OCNC). FeNi@OCNC achieved a current density of 10 ​mA ​cm−2 at a low overpotential of 300.4 ​mV with a very small Tafel slope of 55.4 ​mV dec−1 in 1 ​M KOH, and its activity shows 12 ​h stability. We propose that the coupling effect between Fe, Ni metals is crucial for tuning the electrocatalytic activity, which makes FeNi@OCNC have more oxygen vacancies and higher carbon graphitization degree, thus showing excellent activity. The result may illustrate that bimetallic metal–organic framework-derived carbon nanocubes can be prospective materials for oxygen evolution reaction.

Metal-organic frameworks (MOFs) are attracting more and more attention in the field of electrocatalysis because of their porosity, ease of adjustment and functionalization. Herein, we report the preparation of sulfur-nitrogen dual-doped Co–Fe bimetallic carbon nanotubes (CoFe@SNCN) using MOFs as precursors. The optimized CoFe@SNCN achieves a current density of 10 ​mA ​cm−2 ​at a low overpotential of 306.4 ​mV with a very small Tafel slope of 76.0 ​mV dec−1 in 1 ​M KOH, which is 64 ​mV smaller than that of Co@SNCN (370.4 ​mV) and 48 ​mV smaller than that of Fe@SNCN (354.4 ​mV). Moreover, the catalytic performance remains almost unchanged after 12 ​h. The excellent electrocatalytic performance can be attributed to the synergies between the bimetals and heteroatoms doping, which can greatly improve the electrical conductivity between the metals, promote the transfer of electrons and the exchange of substances, thereby greatly reducing the reaction kinetics and enhancing OER properties. This work may provide a very good solution for the research of a new type of highly efficient stable electrocatalytic oxygen evolution catalyst.