[Zn4(thf)(4)(MeZn)(4)(O(3)SiR)(4)] (R=2,6-iPr(2)C(6)H(3)N(SiMe3)), a compound containing trigonal-planar, tetrahedral, and trigonal-bipyramidal metal atoms: a new route to larger aggregates

Giant Zn14 molecular building block in hydrogen-bonded network with permanent porosity for gas uptake

In situ imidazolate-4,5-diamide-2-olate linker generation leads to the formation of a [Zn14(L2)12(O)(OH)2(H2O)4] molecular building block (MBB) with a Zn6 octahedron inscribed in a Zn8 cube. The MBBs connect by amide-amide hydrogen bonds to a 3D robust supramolecular network which can be activated for N2, CO2, CH4, and H2 gas sorption.

Unique formation of mono-, tetra- and nona-nuclear zinc complexes from protonolysis reactions of [Zn(dmpzm)Et2]

Protonolysis reactions of [Zn(dmpzm)Et(2)] () with acetic or formic acid in different molar ratios gave rise to four mononuclear zinc complexes [ZnEt(dmpzm)(L)] (: L = OAc : L = HCOO) and [Zn(dmpzm)(L)(2)] (: L = OAc;L = HCOO), one nonanuclear zinc complex [Zn(micro(4)-O)(2)(ZnEt)(6)(micro(3)-OAc)(4)(micro'(3)-OAc)(2){Zn(dmpzm)Et}(2)], and one tetranuclear zinc complex [Zn(4)(micro(4)-O)(dmpzm)(3)Et(3)]. Compounds were characterized by elemental analysis, IR spectra, (1)H NMR spectra, and the crystal structures of , were determined by single-crystal X-ray crystallography. In the structures of the central Zn atom is tetrahedrally coordinated by two N atoms of one dmpzm and two C atoms of two Et groups (), or one C atom of one Et group and one O atom of formate ligand, or two O atoms of two acetates. In the structure of , a heptanuclear [Zn(micro(4)-O)(2)(ZnEt)(6)(micro(3)-OAc)(4)] core is connected with two [Zn(dmpzm)Et](+) fragments via a pair of micro'(3)-OAc ligands. Compound consists of a Zn(4)(micro(4)-O) tetrahedron in which three Zn atoms are further saturated by two N atoms from dmpzm ligands and an ethyl group while one Zn center is coordinated by three C atoms from the methylene group of the three dmpzm ligands.

Coordination chemistry of Group 12 metals with phosphorodiselenoates: syntheses, structures and VT 31P NMR study of monomer–dimer exchange equilibrium

The reactions of diselenophosphates, [dsep, (RO)2PSe2-; R = Et, (n)Pr and (i)Pr] with cadmium(II) and mercury(II) perchlorates in a 2 : 1 molar ratio formed compounds of stoichiometry M[Se2P(OR)2]2{M = Cd, R = Et (1), (n)Pr (2), (i)Pr (3); Hg, Et(4), (n)Pr (5), (i)Pr (6)}, and with zinc(II) perchlorates, chalcogen centered tetranuclear clusters, [Zn4(micro4-E){Se2P(OR)2}6]{E = Se, R = Et (7), (n)Pr (8), (i)Pr (9); E = O, R = Et (10), (n)Pr (11), (i)Pr (12)} were formed. All these complexes have been characterized with the help of analytical data, X-ray crystallography (1, 3, 6, 10, 11 and 12), and FAB-mass spectrometry (7-12). Compound 1 is a linear double-chain polymer, in which each pair of Cd atoms is bridged by two dsep ligands; the mercury 6 polymer has a helical chain structure, in which two Hg atoms are bridged by one dsep ligand, and the other ligand chelates the Hg atom. The chelating dsep ligands lie on either side of the helical chain. Compound 3 exists as a dimer in which two cadmium atoms are connected by two bridging dsep ligands, and each cadmium atom is further chelated by a dsep ligand. The metal atoms in 1, 3 and 6 are each coordinated by four selenium atoms in a distorted tetrahedral geometry. Clusters 10-12 have tetrahedral array of zinc atoms with an oxygen atom in the center with edge-bridging dsep ligands. Positive FAB-mass spectra support the formation of selenium-centered clusters,7-9, of which the cluster 8 was structurally confirmed earlier. The solution state behavior of compounds 1-12 has been studied by using multinuclear NMR spectroscopy. Dimer 3 in CD2Cl2 showed monomer-dimer exchange equilibrium in the temperature range 20 to -90 degrees C and the free energy of activation is calculated from the coalescence temperature as DeltaG++(223 K)= 38.5 kJ mol(-1). Polymer undergoes depolymerization in CDCl3 and exhibits monomer-dimer exchange equilibrium in the temperature range 20 to -60 degrees C.

Molecular zinc phosphonates: synthesis and X-ray crystal structures of [{(ZnMe)4(THF)2}{tBuPO3}2] and [{(ZnEt)3(Zn(THF))3}{tBuPO3}4{μ3-OEt}]

The reactions of zinc alkyls with tert-butylphosphonic acid in 2 : 1 and 1 : 1 molar ratios afforded [[(ZnMe)(4-)(THF)2][tBuPO3]2] (2) and [[(ZnEt)3(Zn(THF))3][tBuPO3]4[mu3-OEt]] (3), respectively. Compounds 2 and 3 have been fully characterised by means of spectroscopic and analytical methods. Single-crystal X-ray diffraction studies revealed that zinc phosphonates 2 and 3 are tetra- and hexa-nuclear, respectively. This is in contrast to the dodecanuclear zinc phosphonate [[Zn2(THF)2(ZnEt)6Zn4(mu4-O)][(tBuPO3)8]] (1) obtained in a 1.5 : 1 reaction between zinc alkyls and tBuP(O)(OH)2.