Inorganic Chemistry Communications (v.4, #4)

Contents (iii-iv).

A novel two-dimensional layer network composed of cadmium and bridging isophthalate ligand by Chang-Ge Zheng; Zhen-Feng Chen; Jing Zhang; Ren-Gen Xiong; Xiao-Zeng You (165-167).
The first isophthalate (IPT) ligand bridging cadmium two-dimensional network coordination polymer, Cd2·(IPT)2·(C5H5N)2 (1), was synthesized using 1,3-dicyanobenzene. The IPT adopts a μ5 and μ6-bridging mode and connects with Cd to form the double-layered square grid structure.
Keywords: Cadmium; Isophthalate; Bis-tridentate; Two-dimensional network;

We synthesized a new “4,4-bipyridyl-based” building block, 1,4-(di-4-pyridyl) methoxy benzene (bpmob), which appears as two kinds of isomers: trans- and cis-modes. The building block self-assembled into one-dimensional coordination polymer [Cd(NO3)2(cis-bpmob)2] n ·[Cd(NO3)2(trans-bpmob)(H2O)]2n (I) with Cd(II), and two-dimensional coordination polymer [Co(NCS)2(trans-bpmob)2] n (II) with Co(II). Polymer I consists of two parts: double zig-zag linear chain and ladder-like one-dimensional chain, trans- and cis-modes exist simultaneously in the polymer. Polymer II shows a two-dimensional plane network structure with rhombohedral grids, and the polymer also exhibits layered packing in its solid-state structure.
Keywords: Self-assembly; 4,4-Bipyridyl-based building block; Coordination polymers; Crystal structure;

A new tetranuclear iron(III) complex [Fe4(μ-btppnol)2(μ-O)2(μ-OAc)2](BPh4)2·CH3CN(H2O)1/2(MeOH)1/2 (1), (H2btppnol=N,N,N -tris(2-pyridylmethyl)–N –(2-hydroxybenzyl)–1,3-diaminopropan-2-ol) was synthesized and its crystal structure and magnetic properties are shown. Complex 1 is an interesting structural model for polynuclear iron enzymes, since the ligand H2btppnol is unsymmetric, and thus it may provide distinct coordination modes for the iron centers. The magnetic investigation revealed two antiferromagnetic coupling pathways, one mediated by the oxo bridge, J=−83(6)  cm −1 and the other mediated by the alkoxo bridge, with J=−8.7(5)  cm −1 and similar to the J=−9  cm −1 observed for the oxidized form of purple acid phosphatases.
Keywords: Tetranuclear iron complex; Unsymmetric ligand; Iron enzyme; Terminal phenolate;

Titanium(IV) complexes of trianionic amine triphenolate ligands by Moshe Kol; Marina Shamis; Israel Goldberg; Zeev Goldschmidt; Sima Alfi; Einat Hayut-Salant (177-179).
Two trianionic amine triphenolate ligands are introduced and their isopropoxide Ti(IV) complexes synthesized. The two complexes are mononuclear and C 3-symmetrical on the NMR timescale. High barriers to inversion (ΔG>65  KJ mol −1 ) between the enantiomers of each complex were found. The complex derived from the bulkier tripodal ligand shows a better resistance to hydrolysis.
Keywords: Phenolate ligands; Tripodal ligands; Titanium complexes; X-ray structure;

The reaction between the lithium salt of [closo-1-(C6H5)-1,2-C2B10H10] anion and N-(2-bromoethyl)phthalimide in anhydrous toluene did not result in the expected coupling product, but rather produced an unprecedented carborane species, 1-phenyl-2-[2,3-benzobicyclo(3,3,0)-1-oxo-4-oxa-7-aza-8-yl]-1,2-dicarba-closo-dodecaborane(12) (3), in 63% yield.
Keywords: Phthalimidoethyl; Benzobicyclo; Dicarbadodecaborane; Exo-polyhedral; Substitution;

Reaction of [(CO4Mo(μ-Cl)3Mo(SnCl3)(CO)3] 1 with PhCCPh in inert atmosphere affords the mixture of alkyne halocarbonyl compounds, which after exposure to moist air rearranges to give the complex [Mo33-O)(μ3-Cl)(μ2-Cl)(μ2-OH)2(O)(η 2-PhCCPh5)] 2. The structure of complex 2 was established by X-ray crystallography. The molecule consists of a nearly isosceles triangle of Mo atoms joined by triply bridging oxygen and chlorine atoms. Compound 2 is noteworthy since it is the first trinuclear complex of molybdenum in which a mixed-valence Mo2 IIMoIV core has been established.
Keywords: Molybdenum; Crystal structure; Trinuclear compound; Mixed-valence; Alkyne complex;

Time-resolved near-IR luminescence from ytterbium and neodymium complexes of the Lehn cryptand by Stephen Faulkner; Andrew Beeby; Marie-Christine Carrié; Anjum Dadabhoy; Alan M. Kenwright; Peter G. Sammes (187-190).
The Lehn cryptand has been widely applied to the study and application of luminescent lanthanide ions. We have demonstrated that the ytterbium and neodymium complexes are also luminescent. The luminescence lifetimes of the ytterbium complex fit well to established models for determining the number of inner sphere water molecules. By contrast, the neodymium complex exhibits unusually long lifetimes in aqueous media when compared to those observed with aminocarboxylate ligands. This behaviour may be ascribed to the relatively small number of proximate C–H oscillators in the cryptate.
Keywords: Luminescence; Ytterbium; Neodymium; q values;

The novel C3-chiral tripodal amine HC{SiMe2NH[(R)-1-(p-methoxyphenyl)ethyl]}3 (1) and the corresponding trilithium triamide [HC{SiMe2N(Li)[(R)-1-(p-methoxyphenyl)ethyl]}3] (3) have been synthesized and characterized by X-ray diffraction; the latter was found to have a central adamantoid cage structure in which the two-coordinate Li atoms are internally solvated by the peripheral aryl groups.

Reaction of Co(ClO 4)2  · 6H 2 O with [Zn(dien) (CH3CO2)] n (ClO4) n (dien ≡ diethylene-triamine) in water in a specified proportion leads to the isolation of a novel heterodinuclear complex [(dien)Zn(μ-CH3CO2)(μ-H2O)2Co(dien)](ClO4)3, where the Co(II) centre is low-spin octahedral.
Keywords: Transmetallation; Dinuclear complexes; Cobalt(II) complexes; Zinc complexes; Crystal structures;

The reaction of (Ph2PNH)2CS with nickel(II) chloride hexahydrate in methanol proceeds with methanolysis of a P–N bond to give trans-[Ni{Ph2PNHC(S)NH2–P,S}2]Cl2, whose structure has been confirmed by X-ray crystallography.
Keywords: Nickel; X-ray crystal structure; Phosphine; P–N bond;

Reaction of [PdCl2(CH3CN)2] with HDpyF (HDpyF = bis(2-pyridyl)formamidine) in CH3CN afforded a yellow product [Pd2Cl2(DpyF)2] which was characterized by X-ray crystallography. The DpyF ligand coordinates to the Pd atoms in a new tridentate fashion, forming a chelating and a bridging bonding modes. The molecules are chiral due to the ligand constraints. Spontaneous resolution of the racemic product can be achieved by crystallization of the yellow product in CH3CN/ether, and a CD spectrum can be obtained.
Keywords: Bis(2-pyridyl)formamidine; Dipalladium complex; Spontaneous resolution; Crystal structure;

Planar chiral derivatives of 1,1-diphosphaferrocene with potential application in nonlinear optics by Arkadiusz Kłys; Janusz Zakrzewski; Keitaro Nakatani; Jacques A. Delaire (205-207).
Planar chiral “push–pull” derivatives of 1,1-diphosphaferrocene were obtained in the Knoevenagel reaction starting from racemic or optically resolved 2-formyl-3,3,4,4-tetramethyl-1,1-diphosphaferrocene. Their second-order non-linear optical (NLO) properties were studied by powder tests and the EFISHG technique at 1.907 μm.
Keywords: 1,1-diphosphaferrocene; Planar chirality; Optical resolution; “Push–pull” molecules NLO;

Preparation and characterization of CdS nanoparticles by ultrasonic irradiation by G.Z. Wang; W. Chen; C.H. Liang; Y.W. Wang; G.W. Meng; L.D. Zhang (208-210).
Cadmium sulfide (CdS) nanoparticles of about 3 nm in diameter have been prepared by the sonochemical reduction of a mixed solution of cadmium chloride (CdCl2), sodium thiosulfate (Na2S2O3) and isopropyl alcohol ((CH3)2CHOH) in Ar atmosphere at room temperature. The CdS nanoparticles were characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The formation mechanism of CdS nanoparticles is also discussed together with the optical absorption spectroscopy analysis. The method presented here can be used for the preparation of other sulfide nanoparticles.
Keywords: CdS; Nanoparticles; Sonochemical reduction; Formation mechanism;

The complexation formation between potassium dibenzyldithiocarbamate and 18-crown-6 and the cryptand (2 2 2) was studied in chloroform using calorimetric titrations. By variation of the molar ratio of the salt and water the influence on the reaction enthalpies was studied. With increasing concentration of water in chloroform the values of the reaction enthalpies decrease for both ligands. The microsolvation of the cation or ion pair present in solution by the water molecules has a pronounced effect on the reaction. Thus the presence of very small amounts of water cannot be neglected for the extraction of cations from aqueous to chloroform solution.
Keywords: Microsolvation; Chloroform; Crown ether; Cryptand; Complex formation;

The Fe(III) siderophore cation [ferrioxamine B]+ and oxalate form an ion pair which shows an outer-sphere charge transfer (OSCT) absorption at λ max=262 nm. While ferrioxamine B is not light-sensitive the aqueous ion pair [ferrioxamine B]+ C 2 O 4 2− undergoes a photoreduction to Fe(II) upon OSCT excitation.
Keywords: Electronic spectra; Charge transfer; Photochemistry; Iron complexes; Siderophores;