Absolute structure determination of Berkecoumarin by X-ray and electron diffraction

The absolute structure of Berkecoumarin, a natural product from a Berkeley Pit Lake Penicillium sp. is reported from both X-ray and electron diffraction data.

Synthesis and crystal structure of an iron triazole com­plex resulting from the unexpected ligand cleavage of a triazolium carbene precursor

A triazolium salt in reaction with iron(II) chloride undergoes cleavage of an N-substituent after deprotonation forming an aceto­nitrile­(triazole)iron(II) hexa­chlorido­oxidodiferrate(III) com­plex with the counter-ion having a linear geometry at the O atom.

Borotropic shifting of the hydro­tris­[3-(2-furyl)pyrazol-1-yl]borate ligand in high-coordinate lan­tha­nide com­plexes

The coordination chemistry of the hydro­tris­[3-(2-furyl)pyrazol-1-yl]borate (Tp^2-Fu) ligand is explored with cerium(III) and dysprosium(III). The difference in Lewis acidity of the ions reveals varying stability in the bis-Tp^2-Fu lan­tha­nide com­plexes.

Crystal, electronic structure and hydrogenation properties of the Mg_5.57Ni₁₆Ge_7.43 cluster phase with a new type of polyhedron

The crystal structure of the cubic ternary germanide Mg_5.57Ni₁₆Ge_7.43 has been determined by single-crystal X-ray diffraction. The structure type represents the structure family based on the Th₆Mn₂₃-type and Mg₆Cu₁₆Si₇. A new type of polyhedron, i.e. a penta­conta­tetra­hedron, which is based on triangular, tetra­gonal and penta­gonal faces, is described. Electronic structure and hydrogenation properties are discussed.

Two metastable high hydrates of energetic material 3,3′,5,5′-tetra­nitro-4,4′-bi­pyrazole

Crystallization of 3,3′,5,5′-tetra­nitro-4,4′-bi­pyrazole obeys Ostwald's rule of stages and features the emergence of metastable highly hydrated phases prior to the formation of the stable monohydrate.