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The two-electron reduction of a Group 14-element(I) complex [RË⋅] (E=Ge, R=supporting ligand) to form a novel low-valent dianion radical with the composition [RË:]. 2− is reported. The reaction of [LGeCl] ( 1, L=2,6-(CHNAr)2C6H3, Ar=2,6- iPr2C6H3) with excess calcium in THF at room temperature afforded the germylidenediide dianion radical complex [LGe]. 2−⋅Ca(THF)32+ ( 2). The reaction proceeds through the formation of the germanium(I) radical [LGe⋅], which then undergoes a two-electron reduction with calcium to form 2. EPR spectroscopy, X-ray crystallography, and theoretical studies show that the germanium center in 2 has two lone pairs of electrons and the radical is delocalized over the germanium-containing heterocycle. In contrast, the magnesium derivative of the germylidendiide dianion radical is unstable and undergoes dimerization with concurrent dearomatization to form the germylidenide anion complex [C6H3-2-{C(H)NAr}Ge-Mg-6-{C(H)-NAr}]2 ( 3). [ABSTRACT FROM AUTHOR]

The two-electron reduction of a Group 14-element(I) complex [RË⋅] (E=Ge, R=supporting ligand) to form a novel low-valent dianion radical with the composition [RË:]. 2− is reported. The reaction of [LGeCl] ( 1, L=2,6-(CHNAr)2C6H3, Ar=2,6- iPr2C6H3) with excess calcium in THF at room temperature afforded the germylidenediide dianion radical complex [LGe]. 2−⋅Ca(THF)32+ ( 2). The reaction proceeds through the formation of the germanium(I) radical [LGe⋅], which then undergoes a two-electron reduction with calcium to form 2. EPR spectroscopy, X-ray crystallography, and theoretical studies show that the germanium center in 2 has two lone pairs of electrons and the radical is delocalized over the germanium-containing heterocycle. In contrast, the magnesium derivative of the germylidendiide dianion radical is unstable and undergoes dimerization with concurrent dearomatization to form the germylidenide anion complex [C6H3-2-{C(H)NAr}Ge-Mg-6-{C(H)-NAr}]2 ( 3). [ABSTRACT FROM AUTHOR]

Keywords: metal coordination; metal-organic frameworks; modulator; polymorphism; thorium EN metal coordination metal-organic frameworks modulator polymorphism thorium 17504 17504 1 12/22/21 20211215 NES 211215 B The extraordinary coordination versatility b of the Th SP 4+ sp cation and the unexpected bridging role of formate allows polymorphism control of thorium-organic frameworks (TOFs) with five distinct phases, wherein the highest degree of porosity and interpenetration for TOFs have been achieved. Front Cover: Unveiling the Unique Roles of Metal Coordination and Modulator in the Polymorphism Control of Metal-Organic Frameworks (Chem. Eur. J. 70/2021) Metal coordination, metal-organic frameworks, modulator, polymorphism, thorium. [Extracted from the article]

Cover Feature: Boosting the Iodine Adsorption and Radioresistance of Th-UiO-66 MOFs via Aromatic Substitution (Chem. Eur. J. 4/2021) Keywords: iodine; metal-organic frameworks; radioresistance; substituent effects; thorium EN iodine metal-organic frameworks radioresistance substituent effects thorium 1162 1162 1 01/20/21 20210118 NES 210118 B Effective capture of radioactive iodine b is of paramount importance for the safe and long-term storage of fission products in the nuclear fuel cycle. Iodine, metal-organic frameworks, radioresistance, substituent effects, thorium. [Extracted from the article]

Six novel organotin (IV) complexes, [(Me3Sn)2(H2O)2L] (1), [(R3Sn)2L]n (R = Me 2, R = n‐Bu 3), [(Ph3Sn)2L] (4), [Me2SnL]n (5), [(Me2Sn)2L(μ3‐O)]n (6) have been designed and synthesized by the reactions of 4,4′‐oxybisbenzoic acid (H2L) and triorganotin (IV) chloride or oxide. All the complexes have been characterized by elemental analysis, FT‐IR, NMR, ESI‐Mass, PXRD and X‐ray crystallography. The single crystal diffraction reveals that complexes 1 and 4 represent dinuclear tin monomers. Complexes 2 and 3 display 2D network structure and 2D corrugated framework respectively, which both contain tetranuclear 36‐membered macrocycles. Furthermore, 2D structures are linked into a 3D supramolecular structures through intermolecular C‐H···π interactions. Complex 5 shows 1D infinite helical chain and further constructs 3D ladder supramolecular architecture through additional Sn···O and C‐H···O intermolecular interactions. Complex 6 displays 1D infinite polymeric chain containing 28‐membered macrocyclic ring. Preliminarily in vitro cytostatic activity studies on cervical carcinoma cell lines (HeLa) and hepatocellular carcinoma cell lines (HepG‐2) by MTT assay for some complexes reveal that complexes 3 and 4 exhibit high cytostatic activity. Further, complexes 3 and 4 were selected to investigate interactions of bovine serum albumin (BSA) by fluorescence quenching spectra and synchronous fluorescence spectra, which indicates that the complexes could quench the intrinsic fluorescence of BSA in a static quenching process. [ABSTRACT FROM AUTHOR]

Mechanochemistry is emerging as a powerful solvent ‐ free approach to chemical synthesis. Examples of mechanochemical methodologies in the synthesis of main ‐ group compounds are few and far between. It is shown that ball ‐ milling enables the solvent ‐ free synthesis of a range of phosphazane frameworks with a broad substrate scope, yielding new acyclic and macrocyclic species. Fast, selective and high ‐ yielding product generation from poorly soluble starting materials demonstrates the potential of mechanochemistry as a powerful alternative to solution ‐ based methods in synthetic main ‐ group chemistry. More information can be found in the Full Paper by F. García et al. on page 11279. [ABSTRACT FROM AUTHOR]

A diagram is presented which shows the chemical formula for organo-phosphorus compounds and the syntheses of chiral phosphino-carboxylic acid esters.

The facile phospha-Michael addition provides highly enantioenriched tertiary phosphine adducts. [ABSTRACT FROM AUTHOR]

The first protocol involving the catalytic enantioselective phospha-Michael addition of β,γ-unsaturated α-ketoesters and amides is presented. Synthetically important chiral tertiary phosphines are obtained with excellent enantioselectivities. [ABSTRACT FROM AUTHOR]