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The synthesis of new solvent-separated ion-pair compounds and extended structures containing ytterbium(II)-transition metal isocarbonyl linkages is reported. Findings reveal that the [[Mn[(CO).sub.5]].sup.minus] anion has trigonal bipyramidal geometry and is linked to ytterbium through two equatorial carbonyls.

M-H-B bridges and M...alpha-H-C agostic interactions with Eu(II), Yb(II), and K cations occur in a series of 9-BBN hydroborate, [H(sub2)BC(sub8)H(sub14)](super -), complexes. The preparation, the structural and the spectroscopic characterization of Eu(II) and Yb(II) 9-BBN hydroborates is reported.

Research has been conducted on the cyclic organihydroborate zirconium monocyclopentadienyl complexes. The preparation of these complexes in diethyl ether has been carried out and the details are reported.

Research has been conducted on metallic ytterbium. The transmetalation reaction of this ytterbium with Hg[Co(CO) (sub)4] (sub)2 carried out in tetrahydrofuran and pyridine is described and the results indicate that the reaction products are solvent-separated ion pairs.

Research describes the syntheses of cyanide-bridged lanthanide-transition metal arrays via metathesis reactions involving a lanthanide and a transition metal. X-ray crystallographic analysis suggests that the complexes consist of infinite layers of neutral and puckered sheets.

Research has been conducted on the one-dimensional lanthanide-transition metal complexes. The preparation and characterization of these complexes have been carried out and the results indicate that they crystallize as linear single-strand or double-strand arrays.

A study of the lanthanide-transition-metal complex (H2O)(sub 6)(DMF)(sub 6)Ho2[Ni(CN)(sub 4)](sub 3) which is prepared from the reaction of Ho(NO3)(sub 3).6.5H2O with K2[Ni(CN)(sub 4)] at a 2:3 molar ratio in DMF (DMF = N.N-dimethylformamide) is presented. The results show that the Ho centers are trans-bridged through a [Ni(CN)(sub 4)](super 2-) unit, each Ho center forming an isocyanide linkage with a terminal [Ni(CN)(sub 4)](super 2-) unit, holmium is eight-coordinated.

Research has been conducted on a new type of hexaosmium boride cluster. The thermolysis of H (sub)3 Os (sub)3 (CO) (sub)9-(BCO) is examined.

Results describe structural characterization of two lithium chloride complexes. Data indicate their structural characteristics differ depending on the presence of or absence of water in the compounds.

Research was conducted to examine the procedures for the preparation and the characterization of new cyclic organohydroborate derivatives of zirconocene dichloride. Three approaches were developed for the synthesis of Cp2ZrH((Mu-H)2BC4H8). The first and second procedures implied the possible synthesis of Cp2Zr((Mu-H)2BC4H8)2 but the compound was not formed. The preferential formation of Cp2ZrH((Mu-H)2BC4H8) instead of Cp2Zr((Mu-H)2BC4H8)2 may be due to greater thermal stability of Cp2ZrH((Mu-H)2BC4H8).

The compounds Cp2Zr((mu-H)B(X)CH2Ph)((mu-H)2BX), where X = C5H10, C4H8, have been synthesized by reacting Cp2ZrCl((mu-H)2BX) with PhCH2MgCl. The reactions were performed on a standard high-vacuum line or in a drybox under an atmosphere of nitrogen. Single-crystal x-ray diffraction studies reveal that these compounds have unsupported Zr-H-B bonds. NMR spectra in solution at low temperature support this finding. However, NMR spectra at room temperature show the hydrogen bridge decomposes to Cp2ZrH((mu-H)2BC5H10) and B(C5H10)CH2Ph when X = C5H10 and Cp2ZrH((mu-H)2BC4H8) and B(C4H8)CH2Ph when X = C4H8.

The reactions of trivalent lanthanide cations with the transition metal anions [Ni(CN)4]2-, [Pd(CN)4]2- and [Pt(CN)4]2- are described. Single-crystal x-ray analyses showed that the molecular structures of the complexes have the general formula {(DMF)10Ln2[M(CN)4]3} with different but related one-dimensional structures designated as type A and B. The type A structure showed that the one-dimensional array is produced by translating the repeating unit along the ac diagonals of the lattice. The repeating unit type B is translated only along the crystallographic a axis of the lattice.

Cp2ZrH((mu-H)2BC5H10) and Cp2Zr((mu-H)2BC5H10)2 are produced by the reactions of Cp2ZrCl((mu-H)2BC5H10) with LiH and K(H2BC5H10). The reaction of Cp2ZrCl(CH3) with K(H2BC5H10) yields the methyl-substituted compound Cp2Zr(CH3)((mu-H)2BC5H10), a synthetic approach that prevents side reactions in the direct alkylation of zirconocene organohydroborate complexes. According to proton nuclear magnetic resonance spectroscopy data, intramolecular hydrogen exchange takes place among Zr-H-B hydrogens, terminal H on Zr and Cp hydrogens at elevated temperature in Cp2ZrH((mu-H)2BC5H10).

(9-BBN)B10H13 is produced in high yield from the reaction of 9-Br-BBN with (B10H13)-. Single-crystal X-ray diffraction data show partial insertion of the boron atom of the 9-BBN unit in (9-BBN)B10H13 into the nido-B10 structure and an agostic interaction of the terminal H(5b) on B(5) with B(BBN). Nuclear magnetic resonance spectroscopy data indicate that in Et2O, (9-BBN)B10H13 is converted to (Et2O)(9-BBN)B10H13. When treated with 'Proton Sponge,' (9-BBN)B10H13 produces (PSH)(9-BBN)B10H12, with the boron of the 9-BBN not fully incorporated in the nido-B11 cluster.

A single-crystal X-ray diffraction analysis of the structure of the organodiborane (mu-H)2(BC5H10)2 was conducted. The study also addressed its reactions with nucleophiles and its conversion to the cyclic organohydroborate anion, [H2BC5H10]-. The findings indicate that the anion functions as a facily hydride transfer agent in its reduction of NH3THF and 4-tert-butylcyclohaxanone. The anion also acts as a chelating ligand to form cyclic organohydroborate complexes.

Zirconocene and hafnocene boracyclopentane derivatives were synthesized from [H2B2(mu-H)(mu-C4H8)2]- and the dichloride salt of zirconocene or hafnocene. Hydrogen bonds bind the boracyclopentane ring of the complex to a metal ion. Time-lapsed nuclear magnetic resonance spectroscopy provided information regarding a possible reaction pathway. The molecular structure and crystal structure of the products are presented.

The formation of a new borylidyne cluster from the reaction of (mu-H)2Os3(CO)10 and BH3S(CH3)2 was described. Nuclear magnetic resonance spectroscopy results were similar to the spectra results of iron and ruthenium borylidyne clusters. Bond angles and distances between the osmium and carbon showed the presence of bridging hydrogen atoms. The two types of structures described reflect the role of the transition metal in the position of the bridging hydrogens.

1,7-(SMe2)2B12H10 and 1,12-(SMe2)2B12H10 were produced by heating a steel pressure vessel with an isomeric mixture of B12H10(SMe2)2 to 150 degrees centigrade for 10 hours. Thin layer chromatography was utilized to separate the compounds of the extracted product. Two independently crystallographic molecules (X and Y) were detected when 1,7-(SMe2)2B12H10 crystallizes in the trigonal space group P3221. The X molecule is located on a general position while the Y molecule was located on a two-fold axis.

The isostructural complexes, [(DMF)4EuNi(CN)4] and [(DMF)4EuPt(CN)4] contain divalent lanthanides and transition metal cyanoates. The isostructural compounds are made of one-dimensional ladders of three europium atoms that are bridged by teracyanometalate anions. The one-dimensional parallel ladders have a unit cell packing diagram that extends to the crystallographic b axis of the lattice. The compounds are also composed of capped trigonal prisms of Eu(II) ions and[(DMF)4EuM(CN)4] fragments.

Yb is used in the reduction of Fe3(CO)12 in liquid ammonia to produce the heterometallic complex (NH3)2YbFe(CO)4. The crystalline compounds (CH3CN)3YbFe(CO)4 2 CH3CN and (CH3CN)3YbFe(CO)4 are then derived from the metallic complex in acetonitrile solution and subjected to X-ray crystal structure analyses. Results suggest the presence of Yb-Fe bonds arranged in a sheetlike pattern in the crystals.

Reaction of Al(BH4)3 with (BH4)- produces stable, crystalline solids of ((Ph3P)2N)+ and (Ph3MeP)+ salts of the tetrakis(tetrahydroborato)aluminate anion (Al(BH4)4)-. Multinuclear NMR spectroscopic studies help characterize these salts, and single-crystal X-ray studies facilitate the determination of the structure of (Ph3MeP)(Al(BH4)4). The aluminum compound has an eight-coordinated Al atom and the Al center is surrounded by distorted dodecahedral coordination geometry formed by the eight bridging hydrogens.

Divalent lanthanide cationic species, which are used as molecular precursors for bimetallic films and metal borides and have coordination numbers seven, eight and nine, were synthesized and structurally characterized. Divalent lanthanides such as Sm(II), Yb(II) and Eu(II) behave as precursors when all other ligands are neutral and easily removable. Divalent lanthanides were studied with hydroborate and transition metal carbonylate substrates.

The hydroboration of (mu-H)2Os3(CO)10 in CH2Cl2 with a THF/B2H6 ratio greater than 2/1 yielded (mu-H)3Os3(CO)9(mu3-BCO) or (mu-H 3Os3 CO 9 mu3-C-single bond)3(O3B3O3). The structure of the second cluster consists of a hexagonal B3O3 ring with three triosmium methylidyne cluster units coordinated to it. Moreover, the proposed scheme for the cluster's generation involves the conversion of a terminal carbonyl ligand to a triosmium face-capping carbonyl.

The reduction of B10H14 to (B10H14)2- through liquid-ammonia solutions of Eu and Yb yielded the products (CH3CN)6Yb(B10H14) and (CH3CN)XEu(B10H14) when extracted with CH3CN or C5H5N. The complex (CH3CN)6Yb(B10H14) cystallizes as (CH3CN)6Yb(mu-H 2 B10H12) with a B(6)-H-B bridge bond and a B(5)-H-Yb bridge bond. The reduction of B10H14 by lanthanide amalgams in 1,2-dimethoxyethane (DME) proceeded slower than those in NH3 and produced precipitates contaminated with Hg. The main reaction product is insoluble in DME .

The study concerning isolation, characterization and molecular structure of 1,2-(Me (sub)2 S) (sub)2 B (sub)12 H (sub)10 is presented. Experiments include comparison of the properties of three (Me (sub)2 S) (sub)2 B (sub)12 H (sub)10 isomers.

The ethylidyne cluster (mu-H)3Os3(CO)9(mu3-CCH3) was synthesized by the addition of excess BH3.THF in CH2Cl2 to (mu-H)2Os3(CO)9(mu3-CCO) which involved the reduction of the unique carbonyl to a methyl group. The presence of ethylidine was also confirmed by X-ray crystal structure determination. The molecular structure of the cluster was described to be of triosmium symmetry made up of an Os3 triangle with three bounded carbonyls per Os atom. The observation was parallel with the result from an X-ray powder diffraction analysis.

Reaction between (Et3NH)2(B10H10) and CF3COOH at 60 degrees Celsius produces triethylammonium 2-(acetonitrile)nonahydro-closo-decaborate (1-). X-ray studies and 11B NMR experiments indicate the anion as (2-B10H9NCCH3)- in which CH3CN is substituted for an equatorial hydrogen on boron. Experimental data dispute the report of the formation of (1-B10H9NCCH3)- in a reaction between CH3CN and (B10H10)2-.

The reaction between (dimethylamino)diethylborane and 2,2'-biimidazole produced a mixture of macromolecular species of variable composition. Crystallization in the presence of moisture led to a compound with the composition C24H38B4N8O. The most probable structure of the compound was determined via X-ray analysis to consist of four boron atoms in a tetrahedral symmetry. A dihedral angle of 106.7 degrees is formed by two biimidazole planes. The B-O-B angle is 151(3) degrees and the average bond lengths are 1.605(11) Angstrom (A) for B-N, 1.607(15) A for B-C and 1.422(6) A for B-O.

X-ray analaysis, infrared and nuclear magnetic resonance spectroscopy were used to determine the crystal conformation of (C5H5N 4 Na 2 Fe2 CCO 8). The results showed that the sodium-isocarbonyl linkages formed the two-dimensional sheetlike structure. Additional studies involving the chemical behavior of the complex in dimethylformamide, tetrahydrofuran and acetonitrile were also presented.

The quantum mechanical calculation analysis was performed on a model complex, diborane-benzene cluster, which showed unusual hydrogen bonding like interaction between a borane system and benzene molecules in a molecular crystal. The results from the analysis would provide meaningful guidance for molecular engineering with diborane-benzene as a building block.

9-BBN hydroborate complexes Ti{Mu-H)(sub 2)BC8H14}(sub 3)(THF)(sub 2), Ti(Mu-H)(sub 2)(BC8H14}(sub 3)(OEt)(sub 2), and [K(OEt(sub 2)(4)]-[Ti{(Mu-H)(sub 2)BC8H14}(sub 4) were formed from the reaction of TiCl4 with K[H2BC8H14] in diethyl ether or THF. All these compounds were characterized by single-crystal X-ray diffraction analysis.

The complex Zr(9-BBN)(sub 4)[9-BBN=(mu-H)(sub 2)BC8H14}(sub 4) are synthesized via the reaction of K(9-BBN) with ZrCl(sub 4) in diethyl ether. The structure of the little compound is determined by X-ray and neutron single-crystal diffraction techniques.

Encapsulation complexes formulated as {[La(DMF)(sub 9)](sub 2)[Cu(sub 12)(CN)(sub 18)].2DMF}(sub infinity) and {[Ln(DMF)(sub 8)][Cu(sub 6)(CN)(sub 9)].2DMF}(sub infinity) were obtained from the one-step reaction of LnCl(sub 3) with CuCN and KCN in DMF. They consist of a three-dimensional Cu-CN anionic array with pockets occupied by the cation, [Ln(DMF)(sub x)](super 3+).

The divalent lanthanide 9-BBN hydroborate complexes (THF)4Ln{(mu-H)2BC8H14}2 (Ln = Eu, Yb) are synthesized by a metathesis reaction of (THF)xLnCl2 with K[H2BC8H14]. In addition, abundant studies on Ln(III) tetrahydroborates are also reported.

Research has been conducted on mono- and dihalogenated derivatives of (Me (sub)2 S) (sub)2 B (sub)12 H (sub)10. The synthesis of these compounds carried out from the reactions of 1,7-(Me (sub)2 S) (sub)2 B (sub)12 H (sub)10 with various halogenating reagents is described.

Results clarify previous observations on the structure and exact position of the hydrogen atom in the salts of the title anion compound. The structure reveals disorder in the crystal instead of a partially opened cage architecture. However, because of the disorderly nature of the crystals, the exact location of the 11th hydrogen atom is not ascertained.

The reduction of inner sulfonium salts, thioethers, and sulfones derived from closo-[B12H12](super 2-) by lithium in methylamine are studied. Results indicate that the reduction of inner methylsulfonium salts, thioethers, and sulfones derived from closo-[B12H12](super 2-) by lithium in methylamine produces the corresponding thiols.

The redox reaction of YbCl2 with K2[Pd(CN)4].H2O in DMF has produced a new kind of lanthanide-transition metal complex consisting of a cationic, chain-like array {[(DMF)16Yb6(mu6-O)(mu3-OH)8(mu-CN)(CN)2]6+}. The dianions [Pd(CN)4]2- link the molecular cluster [(DMF)16YB6(mu6-O)(mu3-OH)8]8+ with extra dianions [Pd(CN)4]2- serving as counterions. The structure is stable in alcoholic and aqueous solutions and in air as a solid.

Research has been conducted on the cyanide-bridged lanthanide-transition-metal arrays. The synthesis of these arrays has been carried out and the results indicate that lanthanide nitrates are strong electrolytes and that they dissociate completely in DMF solvent to form simple ions.

The quantitative synthesis of new Yb(III) inorganic arrays, ( DMF 10Yb2 Ni CN 4)3 (1) and ( DMF 10Yb2 Pt CN 4)3 (2) is achieved by reacting YbCl3 with K2M(CN)4 (M = Ni, Pt) in a 2:3 concentration, respectively. The solid state structure of 1 shows two Yb(III) ions cis connected by two Ni(CN)4(super 2-) anions. This results to lozenge-shaped Yb2Ni2 metal centers that are interconnected with Ni(CN)4(super 2-) anions, trans attached to the Yb atoms, thus generating a one-dimensional array. 2 shows the same repeating molecular units but with two inverted parallel running zigzag lines.

The 5-membered borocyclopentane ring in (eta5-C5H5)(sub 2)ZrCl (mu-H)(sub 2) BC4H8 and (eta5-C5H5)(sub 2)HfCL (mu-H)(sub 2)BC4H8 was formed by the disproportionation of the organodiborate anion H2B2(mu-H)(mu-C4H8)2- with zirconocene dichloride and with hafnocene dichloride. The rings were attached to the 16-electron metal center by hydrogen bridge systems. The two products were described to be white solids and not easily decomposed at room temperature under vacuum.

The synthesis and characterization of the complex ( eta5-C5H5 sub 2 TiB6H9)2 are presented. The complex has been prepared by the reaction of K(B6H9) with (eta5-C5H5)2TiCl in tetrahydrofuran. Spectral analysis showed that the compound is a paramagnetic dimer, and the Ti(III) is formally a 17-electron species.

The carbonyl borylidyne cluster H3OS3(CO)9 BCO, consisting of a boron atom which dons a trio of osmium atoms, is synthesized by the hydroboration of unsaturated cluster H2OS3(CO)10, the osmium-rich carbonyl group. The themolytic reaction, which, proceeded by stirring a solution of H3OS3(CO)9 BCO containing 930 milligrams of the solute and 30 ml of toluene at a temperature of 110 degree celsius for 6 days, yields a brown solid and is isolated by rotary evaporation of the solvant. An analysis of the product separated by prep thin layer chromatography (TLC) on silica using X-ray, NMR, IR and mass spectroscopy reveals the presence of HOS4(CO)12BH2 and HOS5(CO)16B, which exhibit a light yellow and reddish brown band respectively, as observed in the spectra.