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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.

A variety of S-alkylated products are prepared by alkylation of methyl thioethers [ MeSB12 H11] (super 2-) (5), [1-(MeS)-2(7,12) -Me2s) B12H10] (super -1) (6-8), and [1,2(7,12)-(MeS)2 B12H10] (super 2-) (9,11) with alkyl halides and tosylates in acetonitrile. Several derivatives of methyl thioethers 5-11 are characterized by single-crystal X-ray diffraction.

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.

A study concerning the synthesis of benzo-fused boron-containing heterocycles is presented. The use of mass spectrometry, NMR spectroscopies and microelemental analysis is discussed.

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 .