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Monocrystals of dinuclear μ‐1,4‐bis(3‐aminopropyl)piperazine‐κ4N1,N1′:N4,N4′‐bis[bis(tri‐tert‐butoxysilanethiolato‐κS)cadmium(II)], [Cd2(C12H27O3SSi)4(C10H24N4)] or [Cd2{SSi(OtBu)3}4(μ‐BAPP)], 1, and polynuclear catena‐poly[[bis(tri‐tert‐butoxysilanethiolato‐κS)cadmium(II)]‐μ‐1,4‐bis(3‐aminopropyl)piperazine‐κ2N1′:N4′], [Cd(C12H27O3SSi)2(C10H24N4)]n or [Cd{SSi(OtBu)3}2(μ‐BAPP)]n, 2, with 1,4‐bis(3‐aminopropyl)piperazine (BAPP) and tri‐tert‐butoxysilanethiolate ligands, were obtained from the same ratio of reactants, but with different solvents used for the crystallization processes. The structures and properties of both complexes were characterized using elemental analysis, X‐ray diffraction and FT–IR, 1H NMR and luminescence spectroscopy. Applied density functional theory (DFT) computational methods and noncovalent interaction (NCI) analysis were used for geometry optimization and visualization of the interactions between the metallic centres and their surroundings. The X‐ray analysis revealed four‐coordinate CdII centres bound to two S atoms of the silanethiolate groups and two N atoms of the BAPP ligand; however, it chelates to tertiary and primary N atoms in 1, whilst in 2 it does not chelate and bonds only to RNH2. The photoluminescence properties of complexes 1 and 2 result from free‐ligand emission and differ significantly from each other with respect to emission intensity. Additionally, antifungal activity was investigated against 18 isolates of fungi. Compound 1 strongly inhibited the growth of three dermatophytes: Epidermophyton floccosum, Microsporum canis and Trichophyton rubrum. [ABSTRACT FROM AUTHOR]

Highlights: [•] X-ray molecular structures of three phenoxysilyl compounds are reported. [•] Vibrational spectra of two polymorphs of phenoxysilanethiol are analyzed. [•] The energy of intramolecular SH---π interaction is estimated from DFT calculations. [•] DFT calculations are in good agreement with experimental results. [Copyright &y& Elsevier]

Highlights: [•] A neutral 1D coordination polymers of Cd(II) and Zn(II) silanethiolates have been synthesized. [•] Metal ions are bridged by bipyridine derivatives bpea and bpey. [•] Crystal structures of polymers show the presence of cavities filled with molecules of solvent. [•] Polymers are stable up to 300°C and display blue emissions. [ABSTRACT FROM AUTHOR]

Abstract: 5-[Hydroxy(aryl/alkylamino)methylene]-2,2-dimethyl-1,3-dioxane-4,6-diones react with BF3·Et2O in mild conditions leading to the formation of boron difluoride complexes of carbamoyl Meldrum''s acids. The X-ray structure has been obtained for one representative complex. The obtained new compounds are air and moisture stable at standard ambient conditions and easily isolable. [Copyright &y& Elsevier]

Abstract: A novel nickel(II) cluster [Ni6(μ-O)6{SSi(tBuO)3}6(H2O)6(NH3)4] 1 has been synthesized in reaction of NiCl2⋅6H2O with tri-tert-butoxysilanethiol and ammonia in water solution. The magnetic measurements show the presence of strong antiferromagnetic interactions between magnetic centers. [Copyright &y& Elsevier]

Abstract: Three heteroleptic, neutral nickel(II) tri-tert-butoxysilanethiolates with monodentate heterocyclic bases (pyridine, 2-methylpyridine and 3,5-dimethylpyridine) serving as additional ligands have been prepared following the same synthetic procedure. The complexes were characterized by single crystal X-ray structure determination and elemental analysis. For complexes 1 and 2, FT-IR and UV–Vis spectroscopy have been additionally recorded. Three different coordination motifs have been observed in these complexes. Molecules building tetragonal crystals of [Ni{SSi(O t Bu)3}2(C5H5N)] (1) feature Ni(II) coordinated by two S,O-chelating tri-tert-butoxysilanethiolato residues and one N atom of pyridine in a strongly distorted trigonal bipyramidal environment. The complex [Ni{SSi(O t Bu)3}2(C6H7N)2] (2) forms triclinic crystals and its core atoms adopt a planar geometry with Ni(II) in the middle of the N2S2 plane. Molecules of complex [Ni{SSi(O t Bu)3}2(C7H9N)2(H2O)] (3) form orthorhombic crystals with penta-coordinated Ni(II) in a distorted tetragonal pyramidal NiN2OS2 environment. Complex 2 roughly mimics one of the two metal centers in the active site of the ACS/CODH enzyme. [Copyright &y& Elsevier]

Five nickel(II) complexes containing aliphatic diamines and tri- tert -butoxysilanethiolate ligand have been synthesized for the purpose of studying their structural, spectral (IR, UV–Vis, HF EPR) and thermal properties. Complexes ( 1 )–( 5 ) have been prepared in high yield by reactions of [Ni{SSi(O t Bu) 3 } 2 (NH 3 )(H 2 O)] with 1.3-propanediamine ( L 1 ), 1,6-hexanediamine ( L 2 ), or 1,7-heptanediamine ( L 3 ). The X-ray structures were determined for complexes [Ni{(SSi(O t Bu) 3 } 2 ( μ -L 1 ) 2 ] ( 1 ), [Ni{(SSi(O t Bu) 3 } 2 ( μ -L 2 ) 2 ] n ( 2 ) and [Ni{(SSi(O t Bu) 3 } 2 ( μ -L 3 ) 4 ] n ( 3 ). Compound ( 1 ) is mononuclear with Ni(II) ions coordinated by two molecules of chelating 1.3-diaminepropane. Complexes ( 2 ) and ( 3 ) consist of 1D polymeric structures with Ni(II) atoms bridged by diamine molecules. The coordinated atoms and the nickel atom form a NiN 2 S 2 square-planar core in polymeric ( 2 ) and a distorted trans -octahedral NiN 4 S 2 core in mononuclear ( 1 ) and polynuclear ( 3 ). Reactions of [Ni{SSi(O t Bu) 3 } 2 (NH 3 )(H 2 O)] with 1,4-butanediamine ( L 4 ) and 1,5-pentanediamine ( L 5 ) resulted in single crystals of compounds ( 4 ) and ( 5 ) which were not suitable for X-ray measurements. The spin Hamiltonian parameters g , D , and E were determined for compound ( 1 ) from high-field HF EPR spectra. [ABSTRACT FROM AUTHOR]