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The reactions of group 2 metal cations with salicylic acid in the presence of pyridine bases are examined and the structural variations are observed based on the ability of the added pyridinic ligand to chelate the metal ions. Chelating 1,10-phenanthroline is incorporated in the coordination sphere, whereas 4,4'-bipyridine has acted as a lattice filler without the coordination to the metal.

A new one-dimensional organic soluble metal-phosphate chain is transformed into a two-dimensional grid structure. All the new metal-organic phosphates are characterized by elemental analysis, thermal analysis and infrared (IR) and NMR spectroscopy and the metaphosphate ceramic materials are characterized by IR spectral and powder X-ray diffraction studies.

Research demonstrates a simple and facile metal-organic precursor method for the preparation of transition metal metaphosphate materials at low temperatures. Results show that the method facilitates the synthesis of a series of new polymeric metal phosphate precursors with a 1:2 M/dtbp ratio.

Research has been conducted on the alkaline earth metals. The synthesis and isolation of the 2,2'-dithiobis(benzoic acid)-group 2 metal ion complexes in the solid state have been carried our and the results of the thermal behavior analysis, spectroscopic characterization and single-crystal X-ray molecular structural determinations of the calcium, barium and strontium complexes are presented.

A study was conducted on the synthesis of heavier alkali metal ions, Na+ and K+, containing gallophosphonates which possess polyhedral framework structures. The findings indicate that the sizes and shapes of the resultant phosphonate cages are dependent on the sizes of the alkali metal ions. Moreover, aggregation of the alkali metal ions and the coordination of endocyclic oxygen atoms do not permit clean cage transformation reactions in the presence of organic crown ethers.

Organometallic fluorides, containing metal atoms bonded with both fluorine and carbon, are useful in catalytic and synthetic chemistry. Despite the presence of strong metal-fluorine bonds, organometallic fluorides can be highly reactive. Organometallic fluorides are used in the production of transition metal complexes with open coordination sites, promoting catalytic reactions. Organometallic fluorides with weakly coordinating anions are useful in the development of chiral Lewis acids.

The development of soft chemical routes, or molecular routes, for the synthesis of advanced materials is becoming more important. The use of discrete silanetriols and several organometallic derivatives as startingmeterials for metallasiloxane cage synthesis has shown good solubility properties. The approach to the synthesis of framework group 13 silicates was extended to isoelectronic phosphate and phosphonate systems. Phosphonate cage molecules of B, A1, Ga and In were synthesized.

The synthesis, structure, and reactivity properties of a novel molecular gallium phosphonate cage which contains flanked lithium ions were presented through analytical and spectroscopic techniques and single-crystal X-ray diffraction study. Data revealed that compound 1 from the first molecular ionic gallophosphonate cage acts as a precursor for the molecular sieves and ion conductors synthesis, unreactive toward air and moisture at room temperature.

Cobalt carbonyl cluster anchored silanetriol was used as the building block for the generation of novel group 13 heterosiloxane frameworks in good yields. The compound has a cubic Al4O12Si4 core with four Co3-(CO)9C cluster units as substituents. Hydroformylation reactions at 120 degrees C under a H2/Co initial pressure of 70 bar involved 1-hexene as substrate. Hydroformylation is presumed to proceed via the decomposition of Co3(CO)9C cluster fragments into Co2(CO)8 units in the case of catalysts Co3(CO)9CSiO3E*THF4 Al and Ga.

A survey of literature published since 1982 on metallasiloxanes prepared from silanediols, disilanols, silanetriols, trisilanols and cyclo(poly)siloxanates is presented. The review, which highlight the synthetic possibilities arising from the development of stable and soluble organosilanols containing two or more hydroxy groups, show the usefulness of incompletely condensed silsesquioxanes as ligands and for silica-supported metal oxide systems.

A new type of a metal-phosphorus acid based layered solid involving N-benzoylphosphoramidic acid is presented. A rare hexacoordination around the metal is observed in the copper phosphoramidate compound due to the amide C=O coordination to Cu in addition to the phosphoramidate P-O coordination and the six-remembered chelate rings present in the copper phosphoramidate compound are made up of five different elements (Cu, P, C, N, and O).

The study shows that it is possible to transform [M(dtbp)2]n (M = Mn, Co; dtbp = di-tert-butyl phosphate), which are one-dimensional molecular polymeric structures, to [M(dtbp)2(bpy)2.2H2O]n (M = Co, Mn) by a very facile soft route by addition of 4,4'-bipyridine (bpy) at room temperature.

The suitability of monoaryl phosphates (RO)P(O)[(OH).sub.2] (R = 2,6-diisopropyl phenyl (dipp[H.sub.2]) and R = 2,6-dimethylphenyl (dmpp[H.sub.2])) in preparing discrete cluster complexes of titanium starting from Cp*Ti[Cl.sub.3] or Ti[(OiPr).sub.4] is studied. The results have described the organic soluble tri-, tetra- and pentanuclear titanium phosphate cages.

The synthesis of alkaline-earth metal phosphates containing nitrogen-donor ligands from the reaction of alkaline-earth metal acetates with 2,6-diisopropylphenyl phosphate in the presence and absence of 1,10-phenanthroline is explained. The presence of a nitrogen donor is shown to improve the cooperativity between the two reacting components.

The calcium 5-amino isophthalate complex is synthesized from an equimolar reaction between {[Ca(O[H.sub.2])4](H2O)} and H2AIP in water. The IR spectrum shows a strong absorption in the region 3200-3500 [cm.sup.-1], indicating the presence of a large number of water molecules in the final product.

Reaction of copper acetate with di-tert-butyl phosphate in pyridine is presented. This reaction yields polymeric [Cu(dtbp)2-(py)2((meu)-OH2)]n as blue hollow tubes.

Research has been conducted on cubic titanosiloxanes. Results demonstrate that these compounds are inert in the reactions with alcohols and acidic hydrogen-containing compounds.

The study includes the synthesis of polyhedral clusters, modulation of structural type of the resulting phosphates, spectral characterization of the products and conversion of the precursor complexes to meta and pyrophosphates. It is observed that the most appealing advantage of employing single-source molecular precursor approach is in its ability to provide atomic level control over a material's composition and homogeneity.

The synthesis of the title compound [Mg (2-aba)(sub 2), [Ca (2-aba)(sub 2)(OH2)(sub 3)]infinity, [{Sr(2-aba)(sub 2)(OH2)(sub 2)}.H2O)]infinity, and [Ba(2-aba)(sub 2)(OH2)]infinity was accomplished by the reaction of MCl2.nH2O with 2-abaH from an aqueous solution. This study undertakes a complete examination of the synthesis and isolation of the group 2 metal complexes in the solid state.

The reactions of RSi(OH)3 (R = (2,6-iPr2C6H3)NSiMe3)(super 5) with phosphorous halides are investigated. The results show that the reaction between a kinetically stabilized organosilanetriol and a highly reactive lambda(super 3)-cyclotriphosphazane offers an easy route to a unique molecular silicophosphonate with abundant acidic hydroxyl groups.

Double-4-ring (D4R) zinc phosphate [Zn(dipp)(DMSO)]4 (1, dipp = 2,6-di-iso-propylphenylphosphate, DMSO = dimethyl sulfoxide), on treatment with a free fluoride ion source, exhibited ability to sense and capture fluoride ions from a variety of sources, as evidenced by extensive solution 31P and 19F NMR spectral titration studies. The fluoride ion-encapsulated cage [nBu4N][F@{Zn(dipp)(DMSO)}4] (2) was isolated in good yield from an equimolar reaction between 1 and nBu4NF in methanol and characterized by analytical and spectroscopic methods. When 1-methyl-4,4'-bipyridin-1-ium fluoride (MeQ-F) was used as the fluoride ion source a zwitterionic cage [F@{Zn4(dipp)4(MeQ)(DMSO)3}] (3) was isolated. Crystal structure determination for 3 confirmed not only fluoride incorporation inside the D4R cage but also a weak interaction of the central fluoride ion with all four zinc centers of the cubane, resulting in a trigonal bipyramidal geometry around the zinc centers. To establish the selectivity, cubane 1 was treated with 2 equiv of MeQ-X (X = various anions) under similar conditions to isolate [F@{Zn4(dipp)4(MeQ)2(MeOH)2}][X] (X = I 4; BF4 5; PF6 6) in good yields. The crystal structure determination of 4 and 5 showed that the iodide and tetrafluoroborate anions are found outside the cage while fluoride ion has entered the cavity. The final fluoride encapsulated D4R cage is anionic in 2, neutral in 3, and cationic in 4-6, showing the versatility of the cubane framework to stabilize fluoride ions in all three forms. NMR titrations showed that 1 can sense even 1 ppm level of fluoride ions and sequester them from fluoridated water and toothpaste extract. [ABSTRACT FROM AUTHOR]

The use of tetrameric zinc phosphate [Zn(dipp)(CH3OH)]4 (1; dipp = diisopropylphenylphosphate dianion) as a suitable building block for realizing new noncovalently linked extended structures, via facile replacement of coordinated methanol molecules by other alcohols, is reported herein. Compounds [Zn(dipp)(sec-butanol)]4·4H2O (2) and [Zn(dipp)(tert-butanol)]4·4H2O (3) have been synthesized by the addition of sec- or tert-butanol to 1 at room temperature. The reaction of zinc acetate or zinc sulfate with dippH2 in the presence of N,N,N′,N′-tetramethylethylenediamine (tmeda) under similar reaction conditions results in the formation of [H2tmeda][Zn4(dipp)4(MeOH)2(OAc)2]·(CH3OH) (4) or [H2tmeda][Zn3(dipp)3(dippH)2(CH3OH)]·(CH3OH)3 (5), respectively. Analytically pure compounds 2-5 have been isolated in the form of single crystals directly from the respective reaction mixtures in very good yields and characterized with the aid of analytical and spectroscopic studies. Single-crystal X-ray diffraction studies reveal that compounds 2 and 3 are neutral tetranuclear zinc phosphates. Compound 4 is also a tetrameric phosphate but is anionic. The core structures of compounds 2-4 resemble the double-4-ring secondary building unit (D4R SBU) in zeolites. Compound 5 is a trinuclear ionic zinc phosphate built from three fused S4R SBUs. Compounds 4 and 5 represent the first examples of discrete anionic zinc organophosphates. The presence of coordinated sec- or tert-butanol molecules and a planar water tetramer cluster in 2 and 3, and the H2tmeda cations and methanol solvents in 4 and 5, leads to the formation of zigzag chainlike supramolecular assemblies in the solid state. [ABSTRACT FROM AUTHOR]

Reactions of 2,6-dimethylphenyl phosphate (dmppH2) and 2,6-diisopropylphenyl phosphate (dippH2) with copper(II) precursors have been investigated in the presence of auxiliary N-donor ligands, and new structural types of copper phosphates have been isolated. Copper acetate reacts with dmppH2 in the presence of either 3,5-di-tert-butyl pyrazole (dbpz) or 3,5-dimethyl pyrazole (dmpz), leading to the isolation of tetrameric complex [Cu(dmpp)(dbpz)]41 and hexanuclear cage complex [Cu6(PO4)(dmpp)3(OAc)3(dmpz)9] 2, respectively. Whereas compound 1 is a cubane-shaped cluster whose Cu4O12P4 core resembles the double-4-ring (D4R) zeolite SBU, compound 2 is a novel hexanuclear copper complex with an unprecedented structure in metal phosphate chemistry. Use of bulkier dippH2 in the above reactions, however, yielded metal-free acid−base complexes [(dippH)(dbpz)(dbpzH)] 3 and [(dippH)(dmpz)(dmpzH)] 4, respectively. The reactions carried out between copper acetate and dmppH2 or dippH2 in the presence of chelating ligand 1,10-phenanthroline produced structurally similar dimeric copper phosphates [Cu(phen)(dmpp)(CH3OH)]2·2CH3OH 5 and [Cu(phen)(dipp)(CH3OH)]2·2CH3OH 6 with a S4R SBU core. Changing the copper source to [Cu2(bpy)2(OAc)(OH)(H2O)]·2ClO4 and carrying out reactions both with dippH2 and with dmppH2 result in the formation of trinuclear copper phosphates [Cu3(bpy)3(dmpp)2(CH3OH)3]·2ClO4·2CH3OH 7 and [Cu3(bpy)3(dipp)2(CH3OH)3]·2ClO4·2CH3OH 8. The three copper ions in 7 and 8 are held together by two bridging phosphate ligands to produce a tricyclic derivative whose core resembles the 4=1 SBU of zeolites. Compounds 1−8 have been characterized by elemental analysis and IR, absorption, emission, and EPR spectroscopic techniques. The crystal structures of compounds 1, 2, 4, 5, 6, and 8 have also been established by single-crystal X-ray diffraction studies. Structurally diverse, oligomeric copper arylphosphate complexes have been synthesized by varying the aryl substituent on the phosphate ester, the ancillary ligand, the organic substituents on the auxiliary ligands, and the source of the metal ion. The dimeric, tetrameric, and trimeric copper phosphates reported in this study serve as useful, suitable model compounds for the S4R, D4R, and 4=1 SBUs of zeolites, respectively, that incorporate transition-metal ions. [ABSTRACT FROM AUTHOR]