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Treatment of [Et4N][Tp*WS3] (1) (Tp* = hydridotris(3,5-dimethylpyrazol-l-yl)borate) with 2 equiv of AgSCN in MeCN afforded a novel neutral compound [(Tp*WS2)2(μ-S2)] (2). Reactions of 2 with excess CuX (X = Cl, Br, I) in MeCN and CH2Cl2 or CHCl3 formed three neutral W/Cu/S dusters [{Tp*W(μ3-S)3Cu3(μ-Cl)}2Cu(μ-Cl)2(μ7-Cl) (MeCN)]2 (3), [{Tp*W(μ3-S)3Cu3}2Br(μ-Br)2(μ4-Br)- (MeCN)] (4), and [{Tp*W(μ3-S)3Cu3}2{Cu2(μ-I)4(μ3-I)2}] (5), respectively. On the other hand, treatment of 2 with CuX (X = Cl, Br) in the presence of Et4NX (X = Cl, Br) produced two anionic W/Cu/S clusters [Et4N][{Tp*W(μ3-S)3Cu3X}2 (μ-X)2(μ4-X)] (6, X = Cl; 7 X = Br). Compounds 2-7 were characterized by elemental analysis, IR., UV-vis, ¹H NMR, electrospray ionization (ESI) mass spectra, and single-crystal X-ray crystallography. The dimeric structure of 2 can be viewed as two [Tp*WS2] fragments in which two W atoms are connected by one S22- dianion. Compounds 3-7 all possess unique halide-bridged double cubanelike frameworks. For 3, two [Tp*W(μ3-S)3Cu3]2+ dications are linked via a μ4-Cl- bridge, two μ-Cl- bridges, and a [Cu(MeCN)(μ-C1)2]+ bridge. For 4, one [Tp*W(μ3-S)3Cu3(MeCN)]2+ dication and one [Tp*W(μ3-S)3Cu3Br]+ cation are linked via a μ4-Br- and two μ-Br bridges. For 5, the two [Tp*W(μ3-S)3Cu3]2+ dications are bridged by a linear [(μ-l)2Cu- (μ3-I)2Cu(μ-I)2]4+ species. For 6 and 7, two [Tp*W(μ3-S)3Cu3X]+ cations are linked by μ4-X- and two μ-X- bridges (x = Cl, Br). In addition, the third-order nonlinear optical (NLO) properties of 2-7 in MeCN/CH2C12 were investigated by using femtosecond degenerate four-wave mixing (DFWM) technique. [ABSTRACT FROM AUTHOR]

Two types of new organically templated mixed-metal sulfites, namely, [H[sub2]pip][NaZn[sub2]Cu(SO[sub3])[sub4]] (1) and [H[sub2]pip] [CdCu[sub4](SO[sub3])[sub4]] (2) (pip = piperazine), have been synthesized under hydrothermal conditions and structurally characterized. Both compounds exhibit a novel 3D mixed-metal inorganic framework with organic template molecules occupying the tunnels of the inorganic skeleton. Compound 1 features a 2D Zn[sub2]Cu(SO[sub3])[sub4][sup3+] layer parallel to the ac plane in which the 1 D chains of Zn(S03)22 anions along the c axis are interconnected with the Cu[sup+] ions via Cu-S bonds. Neighboring Zn[sub2]Cu(SO[sub3])[sub4][sup3-] layers are further interconnected by bridging Na[sup+] ions via Na-O-S bonds into a 3D network, forming 1D tunnels along the a axis which are occupied by the doubly protonated piperazine cations. Compounds 2 features a novel 3D inorganic framework of CdCu[sub4](SO[sub3])[sub4][sup2-] with 2D layers based on Cu[sub4](SO[sub3])[sub4][sup4-] cubanelike clusters. The cluster layers are further interconnected by Cd(ll) ions, forming 1 D tunnels of eight-membered rings along the c axis in which the piperazine template cations are located. Luminescent property measurements as well as band structure calculations based on density functional theory methods were also made. [ABSTRACT FROM AUTHOR]

Herein we report the surfactant-thermal method to prepare two novel one-dimensional mercury selenidostannates, [DBUH]2[Hg2Sn2Se6(Se2)] ( l ) and [DBUH]2[Hg2Sn2Se7 ] (2), where DBU = 1,8- diazabicyclo [5.4.0]undec-7-ene, by applying PEG-400 as the reaction medium. It is worth noting that 1 is kinetically stable and can be transformed into thermodynamically stable phase 2 under a longer reaction time. Our strategy "growing crystalline materials in surfactants" could open a new door to preparing novel crystals with diverse structures and interesting properties. [ABSTRACT FROM AUTHOR]

The synthesis of four novel heteroleptic dipyrrinato complexes [(rj6- arene)RuCl(2-pcdpm)] {rf-arene = C6H6, 1; C10HI4, 2) and [(5-C5Me5)MCl(2-pcdpm)] (M = Rh, 3; Ir, 4) containing a new chelating ligand 4-(2-methoxypyridyl)-phenyldipyrromethene (2-pcdpm) have been described. The complexes 1--4 have been fully characterized by various physicochemical techniques, namely, elemental analyses, spectral (ESI-MS, IR, *H, 13C NMR, UV/vis) and electrochemical studies (cyclic voltammetry (CV) and differential pulse voltammetry (DPV)). Structures of 3 and 4 have been determined crystallographically. In vitro antiproliferative and cytotoxic activity of these complexes has been evaluated by trypan blue exclusion assay, cell morphology, apoptosis, acridine orange/ethidium bromide (AO/EtBr) fluorescence staining, and DNA fragmentation assay in Dalton lymphoma (DL) cell lines. Interaction of 1--4 with calf thymus DNA (CT DNA) has also been supported by absorption titration and electrochemical studies. Our results suggest that in vitro antitumor activity of 1--4 lies in the order 2 > 1 > 4 > 3. [ABSTRACT FROM AUTHOR]

Binuclear zinc(II) and copper(II) complexes based on a new Schiff base ligand N,N'-bis(2-hydroxybenzilidene)-2,4,6-trimethylbenzene-1,3-diamine (H2L) have been synthesized. The ligand H2L and complexes under investigation have been characterized by elemental analyses, spectral (FT-IR, 1H, 13C NMR, ESI-MS, electronic absorption, emission), and electrochemical studies. The structures of H2L and complexes [{Zn(C23H18N2O2)}2] (1) and [{Cu(C23H18N2O2)}2]·H2O (2) have been determined crystallographically. Selective "On-Off-On" switching behavior of the fluorescent complex 1 has been studied. The fluorescence intensity of 1 quenches (turns-off) upon addition of Cu2+, while enhances (turns-on) in the presence of Ag+ ions. The mechanisms of "On-Off-On" signaling have been supported by 1H NMR, ESI-MS, electronic absorption, and emission spectral studies. Job's plot analysis supported 1:1 and 1:2 stoichiometries for Cu2+ and Ag+ ions, respectively. Association and quenching constants have been estimated by the Benesi-Hildebrand method and Stern-Volmer plot. Moreover, 1 mimics a molecular keypad lock that follows correct chemical input order to give maximum output signal. [ABSTRACT FROM AUTHOR]