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Three new polymeric silver cyanide complexes AgCN·AgF·4AgCF3CO2·2CH3CH2CN (3), AgCN·AgCF3CF2CO2 (4) and AgCN·2AgCF3SO3·H2O (5) have been obtained by dissolving AgCN in an aqueous solution of AgX (X=CF3CO2, C2F5CO2 or CF3SO3) and AgBF4, and their layer-type crystal structures determined by X-ray crystallography. In the silver-rich environments, all the co-existing ancillary anions display unusual coordination modes: μ4-O,O,O′,O′-trifluoroacetate and pentafluoropropionate and μ4-η1κO:η1κO′:η1κ2O″-triflate. The cyanide ion functions as a μ3-η1κ2C:η1κN bridge in the construction of an unprecedented chain-like [Ag2(CN)]∞ motif in 4. [Copyright &y& Elsevier]

The new flexible double betaine 1,4-bis(2-picolyloxyl)benzene-N,N′-diacetate (L) has been synthesized and used to generate five complexes with divalent metal chlorides: [M(H2O)6]Cl2·L·2H2O (M=Mn (1), Co (2)), [Cu(μ-L)Cl2]∞ (3), {[Zn(μ-L)Cl2]·2H2O}∞ (4), and {[Cd2(μ-Cl)2(μ-L)Cl2(H2O)2]·2H2O}∞ (5). Isomorphous compounds 1 and 2 have a hydrogen-bonded three-dimensional network in which adjacent L ligands overlap through π–π stacking of the pyridine and benzene rings. Compounds 3, 4, and 5 display three different types of one-dimensional polymeric structures. Bridged by L acting in the anti mode, compound 3 exhibits an infinite zigzag chain in which consecutive, approximately planar L ligands are arranged in a crossed manner when viewed along the chain direction, the distance between adjacent copper(II) ions being about 13 A˚. In contrast, compound 4 features a spring-like infinite helical chain with zinc ions lying on the axis and bridged by L acting in the syn fashion, and the Zn(II)⋯Zn(II) separation is approximately 9 A˚. In compound 5, the building unit is a centrosymmetric Cd2Cl2 moiety, and adjacent dimeric units are linked by the centrosymmetric L ligand acting in the anti mode to give an infinite zigzag chain running along the c axis; such chains are further connected through hydrogen bonds to form a three-dimensional network. [Copyright &y& Elsevier]

Abstract: The phosphorescent silver(I)–gold(I) cluster complex [CAu6Ag2(dppy)6](BF4)4 (N1) selectively stains the nucleolus, with a much lower uptake in the nucleus and cytoplasm, and exhibits excellent photostability. This Ag–Au cluster, which has a photoluminescent lifetime of microseconds, is particularly attractive as a probe in applications of time-gated microscopy. Investigation of the pathway of cellular entry indicated that N1 permeates the outer membrane and nuclear membrane of living cells through an energy-dependent and non-endocytic route within 10 min. High concentrations of N1 in the nucleolus have been quantified by inductively coupled plasma atomic emission spectroscopy (ICP-AES) and transmission electron microscopy coupled with an energy dispersive X-ray analysis (TEM-EDXA), which also helped to elucidate the mechanism of the specific staining. Intracellular selective staining may be correlated with the microenvironment of the nucleolus, which is consistent with experiments conducted at different phases of the cell cycle. These results prove that N1 is a very attractive phosphorescent staining reagent for visualizing the nucleolus of living cells. [Copyright &y& Elsevier]