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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.

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.