Construction of a novel Zn-Ni trinuclear Schiff base and a Ni2+ chemosensor.

A novel Zn-Ni heterotrinuclear Schiff base compound bearing acacen(2-) moieties was constructed through the selective assembly of a chemosensor Schiff base zinc compound with a Ni(2+) ion. Its crystal structure not only clearly explains the binding mode between the chemosensor molecule and the detected metal ion but also represents the first trinuclear complex based on a symmetric acacen(2-) base Schiff base.

Conversion of nonporous helical cadmium organic framework to a porous form.

Two novel cadmium-organic frameworks containing achiral helical nanotubular channels, [Cd(HImDC)(S)](n) (S = Im(1) and Py(2)), have been synthesized and characterized using single crystal X-ray diffraction, in which 1 converts to 2 upon refluxing 1 in pyridine solution with noticeable porosity and hydrogen uptake at medium pressure.

Methyl 2-[(4-chloro-2-meth-oxy-5-oxo-2,5-dihydro-furan-3-yl)amino]-acetate.

The title compound, C(8)H(10)ClNO(5), was obtained via a tandem Michael addition-elimination reaction of 3,4-dichloro-5-meth-oxy-furan-2(5H)-one and glycine methyl ester in the presence of triethyl-amine. The mol-ecular structure contains an approximately planar [maximum atomic deviation = 0.010 (2) Å] five-membered furan-one ring. The crystal packing is stabilized by inter-molecular N-H⋯O and weak C-H⋯O hydrogen bonding.

Poly[[tetra-aquadi-µ(3)-oxalato-µ(2)-oxalato-diprasedymium(III)] dihydrate].

In the title compound, {[Pr(2)(C(2)O(4))(3)(H(2)O)(4)]·2H(2)O}(n), the three-dimensional network structure has the Pr(III) ion coordinated by nine O atoms in a distorted tricapped trigonal-prismatic geometry. The coordinated and uncoordinated water mol-ecules inter-act with the carboxyl-ate O atoms to consolidate the network via O-H⋯O hydrogen bonds.

Tris(2-hydroxy-ethyl)ammonium 1,3-benzo-thia-zole-2-thiol-ate.

In the title compound, C(6)H(16)NO(3) (+)·C(7)H(4)NS(2) (-), the cations and anions are connected by O-H⋯N and O-H⋯S hydrogen bonding. Weak C-H⋯O hydrogen bonding between adjacent cations helps to stabilize the crystal structure.

8-(Carboxy-methoxy)-quinolinium nitrate monohydrate.

In the title compound, C(11)H(10)NO(3) (+)·NO(3) (-)·H(2)O, the planar 8-carboxy-methoxy-quinolinium cation, the nitrate anion and the water mol-ecule are dimerized by hydrogen bonds into square building-block units, and then further assembled into two-dimensional gently undulating supra-molecular layers.

[Determination of trace manganese by non-organic solvents extraction catalytic spectrophotometry in Mn(II)-H2O2-EBT-PEG-2000 system].

A new non-organic solvents extraction catalytic spectrophotometric method for the determination of trace amounts of manganese was studied. The method is based onthe manganese (II) catalyzing hydrogen peroxide to oxidate o f eriochrome black T in hydroxide-ammonium chloride buffer medium. The reaction time and the degree of indicating reaction are controlled by non-organic solvents extraction equilibrium using polyethylene glycol-2000. The absorbance of polyethylene glycol-2000 phase is measured at 539 nm in weak acidic medium. The calibration graph is linear for 0.0080-0.55 microg x mL(-1) Mn (II), and the detection limit is 3.0 x 10(-9) g x L(-1). The method can be applied to the determination of trace manganese in tea and aluminum alloy with satisfactory results.