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The coordination behavior of [{CpMo(CO)(sub 2)}(sub 2)(mu,eta(super 2-)Sb(sub 2))](cp =cyclopentadiene) toward Cu(I) was investigated. Its reaction with AgNO(sub 3) or CuX (X = CI, Br, and I) resulted in the formation of monodimensional polymers.

The reaction of Cl3PNSiMe3 with primary lithium amides is a simple synthetic route to a variety of amino/iminophosphoranes of the type (RNH)3PNSiMe3 (R=alkyl). Further reaction of such species with (super n)BuLi under mild conditions produce the unsymmetrical tetraimidophosphates {Li3[P(NR)(sub 3-)(NSiMe3)]}.

Quantitive yields of [((super t)BuNH)Te(mu-N(super t)Bu)2Te(N(super t)Bu)][OSO2CF3] is obtained by the treatment of [((super t)BuNH)Te(mu-N(super t)Bu)2Te(N(super t)Bu)] with HCF3SO3. The study reports about the crystal structures of the partially hydrolyzed products such as [((super t)BuIN)Te(mu-N(super t)Bu)2Te(mu-O)]2(I3)2, [((super t)BuMeN)Te(mu-N(super t)Bu)2Te(mu-O)]2(I3)2, and [((super t)BuMeN)Te(mu-N(super t)Bu)2Te(mu-O)]2(I3)2.2MeCN.

The synthesis of supramolecular copper hydroxide tennis balls by self-assembly is described. The structure of this compound was determined by using X-ray crystallography.

Research has been conducted on phosphonate dianions' dilithium salts. The studies of these salts demonstrate that they can be produced via lithiation of [PhP(E)(N (super)t Bu) (sub)2] (super)2- with n-butylithium.

Research has been conducted on the thiolate ligand. The use of the electron-rich iron-tiolate complex in investigating the effects of Fe-S(R)...H-X interactions on the donor properties of this ligand in the low-dielectric solvents is described.

Research has been conducted on the Grignard reagent 2,6-Et (sub)2 C (sub)6 H (sub)3 MgI(THF) (sub)n which undergoes rapid aryl exchange in the THF solution. The rapid conversion of this compound, its disolvation to the three-coordinate diarylmagnesium species and the THF solvated magnesium iodide compound structures have been investigated and described.

Research demonstrates that the formation of the transient [Ms(sub)3(SR)](sup)- as [PPh(sub)4][WS(sub)3(SR)] salts containing (R = (sup)iBu, (sup)iPr, (sup)iBu, benzyl, allyl) involves alkylation of [MS(sub)4](sup)2- in which M = Mo or W. Nuclear magnetic resonance spectrosopic analysis reveal the stability and decomposition pathways of the salts into polythiometalates, organic sulfides, and thiols.

Research has been conducted on m-terphenyldichlorophosphanes. The reaction between this compound and excess NaN (sub)3 in acetonitrile at room temperature has been investigated and the results are described.

The initial results of the investigations of cyclic silazanes as substrates for the synthesis of novel silyl substituted aluminum hydrides and the thermolysis of two of the products are described. The reaction of H3Al.NMe(sub 3) with [Me(sub 2SiNH](sub 3) afforded new aminolysis products in good to moderate yields.

Research demonstrates the synthesis of alcohol complexes of osmium nitrosyl porphyrins for the first time. Data reveal that these heme-containing biomolecules undergo facile deprotonation mediated by pyridine to yield cognate alkoxide derivatives.

The reaction of Li(sub 2)Nnaph) (naph = 1-Naphthyl) with SiCl(sub 4) produces (EtO.Li)(sub- 4)[Si(Nnaph)(sub 4)] the first complex containing a tetrakisimidoorthosilicate tetraanion which was characterized via reactions with (super 1)BuNH(sub 3)Cl and MeO-(sub 3)SCF(sub 3) to give Si[N(H)naph](sub 4) and Si[N(Me)naph)(sub 4).

Research has been conducted on the eight- and 16-membered cyanuric-sulfanuric ring systems. The preparation of these systems in good yields via sulfur(IV) system reaction with m-chloroperbenzoic acid is discussed.1

Research has been conducted on the addition of the methyllithium to alkyl isothiocyanates to produce lithium thioamidates. The characterization of the compounds has been carried out.

Research has been conducted on the tellurium diimide dimer. The use of THF as a solvent to synthesize this dimer is described.

Research has been conducted on the rhenium complexes that contain sterically-hindered ligands. The synthesis and electrochemical properties of these complexes are described.

Research has been conducted on the tellurium diimide dimer coordination complexes. Mono- and dimethylation of the complexes have been demonstrated via (super)1 H and (super)125 Te NMR spectroscopy.

Results demonstrate preparation of monometallic thiolate-thiol complexes of ruthenium nitrosyl porphyrins and their bimetallic mu-dithiolate derivatives. Structural analyses indicate that these metalloporphyrins are useful in oxidation and electrophilic chemistry.

A study concerning the synthesis of complexes that involve lithium amidinates and lithium salts is presented. Experiments include crystallographic characterization of the complexes.

Research has been conducted on SeCl (sub)2 solutions in THF or dioxane. The syntheses of these solutions and characterization by (super)77 Se NMR and Raman spectra is described.

A study showed that the reactivity of platinum(IV) complexes toward guanosine 5'-monophosphate follows the order of cathodic reduction potentials. A possible mechanism provided is that there is an initial substitution of one Cl/Pv by a 5'-GMP molecule followed by a two-electron reduction characterized by exponential decay. The formation of the Pv intermediate by substitution was a slow process and was catalyzed by a small amount of cis-[Pt(super IV)(NH3)2(CL2)], implicating the occurrence of a Pt-assisted substitution reaction.

A study was conducted to analyze the synthesis and structural features of the adduct (Li(P(N(super t)Bu)2))4.O.25P4(N(super t)Bu)6 from a reaction in toluene. The solvents were dried and distilled before usage. The Bruker AMX 400 spectrometer was utilized to obtain the nuclear magnetic resonance spectra. Experimental results indicated that the identity of the reaction product was dependent on the solvent and order of addition of the reagents.

Research was conducted to examine the regiospecificity of the reaction of Cl3C2N3S with nucleophiles, the preparation and spectroscopic characterization of Cl2C2N3S(OC6H4C6H5-2) and C2N3S(OR)3, the synthesis and spectroscopic characterization of Cl3C2N3S(O), attempted ring-opening polymerization of Cl3C2N3S and Cl3C2N3S(O) and a novel thermal isomerization of (CF3CH2O)3-C2N3S(O). Results indicate that the reaction of the Cl3C2N3S with sodium alkoxides or aryloxides takes place regiospecifically at sulfur and trisubstitution without ring degradation.

The synthesis and characterization of three novel tris-bridged cyclic thioether ditungsten(III) complexes were described. In addition, the possibility of nucleophilic attack resulting from the ring-opening of the complexes Cl3W(mu-L)3WCl3 and (Cl3W(mu-L)2(mu-Cl)WCl3)- (L = 1,4-dithiane, 1,4-thioxane, pms = pentamethylene sulfide) was investigated. Experimental results showed a significant change in the tris:bis product distribution ratio following the integration of heteroatoms into the thioether ring.

C-nitroso compounds bind the the metal centers in heme-containing biomolecules and are the subject of many studies. The coordination chemistry of ArNO compounds with the group 8 metalloporphyrins as synthetic heme models is considered. The synthesis and spectroscopic characterization of several osmium nitrosarene porphyrin complexes are reported, and single-crystal x-ray diffraction has been used to determine their solid-state molecular and crystal structures.

Nitrosamines belong to the N-nitroso group of compounds and are generally thought to be carcinogenic. A recent communication reported that diethylnitrosamine binds to Fe(III) and Ru(II) porphyrins by a unique O-binding mode. The findings are reported in more detail and it is shown that such nitrosamine binding could be expanded to include osmium porphyrins.

Oxidation of the chair form of Ph4P2N4(SR)2 and the boat form of Ph4P2N4(SMe)2 with MCPBA yields the hybrid sulfanuric-phosphazene ring systems trans-Ph4P2N4(S(O)R)2 and cis-Ph4P2N4(S(O)Me)2, respectively. Twist-boat conformations are assumed by the P2N4S2 rings in these sulfur(VI) heterocycles. R4P2N4(SNMe2)2 is produced from the reduction of R4P2N4(SCl)2 with 2 equiv of Me3SiNMe2, wherein the eight-membered ring has either a chair or distorted chair structure.

A study was conducted on the reaction chemistry of osmium porphyrins with thionitrites and alkyl nitrites as well as the mode of interaction of RSNO with osmium porphyrins. The findings indicate that the reactions of thionitrites and alkyl nitrites with OsII porphyrins result in nitrosyl thiolates and alkoxides. However, in the case of OsIII, the isolation is limited to the osmium nitrosyl difluorophosphate complex.

Research was conducted to examine the synthesis, characterization and protonation of an amide-containing thiolate complex of a ruthenium nitrosyl porphyrin. The objective was to show that the unique trans-addition process also exists for such tertiary alkyl RSNO ligand. The amide-containing RSNO ligand, which is soluble in organic solvents, was chosen to demonstrate that protonation of the resulting (OEP)Ru(NO)(SR) produces a new cationic ruthenium amide adduct. Results reveal that a tertiary alkyl thionitrite adds to a ruthenium porphyrin to yield the nitrosyl thiolate trans-addition product.

An experiment was conducted to study a family of seven-membered dithiadiazepinyl radicals. Density functional theory calculations were used to examine the electronic structure of the parent system. The capability of the radicals to be used as building blocks for molecular conductors was calculated by comparing their dimerization and disproportionation energies with those of the dithiadiazolyl and dithiazolyl radicals. However, the thermal instability of the radicals hindered the possibility of isolating them into pure samples.

Chemical research has established a method of synthesizing new iminophosphide/phosphinoamide anions from the deprotonation of aminodiphenylphosphines. The chemical structures of iminophosphide/phosphinoamide ions lithium (meopentyl)(diphenylphosphino)amide, lithium(isopropyl)(diphenylphosphino)amide and lithium (2,4,6-tri-tert-butylphenyl)(diphenylphosphino)amide are described.

Chemical research shows that thionitrites and isoamyl nitrite react with Fe, Ru and Os porphyrins creating five-coordinate or six-coordinate derivatives. The crystal structures of (por)M(CO) are described. The S-nitroso-N-acetyl-L-cysteine methyl ester with (tetraphenylporphyrinato dianion)Fe(THF)2 produces tetraphenylporphyrinato dianion in high yield.

The x-ray structures and synthesis of the eight-membered rings and the new sixteen-membered rings of heterocycles were described. The reaction of 4-XC6H4CN2(SiMe3)3 (X=Br,CF3) with PhSCl at 100 degrees yields the eight-membered rings and sixteen-membered rings. The C4N8S4 ring has a cradle-like structure with S4 symmetry. Density functional theory calculations revealed that boat and chair conformers of the C2N4S2 ring have similar energies. The anion (HC)2N4(SH)2 super2- should exhibit transannular S-S interactions.

The X-structure of eight phi-electron dications such as Et4P2N4S2Cl2 and [Et4P2N4S2][AlCl4] was analyzed to determine the conformation and steric characteristics of the E2N4S2 ring. The dications are composed of an eight-membered E2N4S2 ring with a distorted boat geometry in which the phosphorus atoms are located on the prow and stern positions. Furthermore, significant differences in geometrical parameters were detected due to unequal S-Cl bond distances.

Five-coordinate (P)Co(NO) complexes were produced by the reaction of four-coordinate (P)Co compounds with nitric oxide at room temperature. The solid-state (P)Co(NO) complexes are stable in air and undergo decomposition in 2-3 weeks. The compounds are diamagnetic with a metalloporphyrin core. The NO ligands of the complexes are composed of a 24-atom porphyrin ring that displaces the Co atom. The cobalt nitrosyl porphyrin, (TPP)Co(NO), also exhibits a bent Co-N-O linkage while (P)Fe(NO) compounds display Fe-N-O bonds angles that ranges from 131-151 degrees.

The structural isomers of the sulfur(II)-containing diazenes with PhSN=C(Ar)=NSPh (Ar = 2-BrC6H4) is characterized by an E,E,E geometry. X-ray analysis of the Z,E,Z isomers indicates the presence of a weak intramolecular sulfur-nitrogen bond which is stabilized by intramolecular E-N interactions. The interaction is characterized by back-donation between the phi lone pairs of the chalcogen and the phi*(N=N). Furthermore, the electron donation between the sigma(N) lone pairs and the sigma*(E-X) and sigma*(E-N) orbitals were also exhibited by the interaction.

The reaction between tert-BuNHLi and TeCl4 in a 4:1 ratio yields thermally stable Te-N compounds. The tellurium diimide dimer, Te2(Ntert-Bu)4, is bonded through an exocyclic nitrogen atom to LiTe(Ntert-Bu)2(NHtert-Bu), to form the most important centrosymmetric complex. The complexes have an ability to dimerize due to the presence of Te-N multiple bonds. The variable temperature 1H- and 7Li-NMR spectra and X-ray crystallography reveal some weak Te-N bonds since rapid proton shifts are observed. The mechanisms for the fluxional processes in these complexes is also discussed.

The approximate density functional theory is used in conjunction with spectroscopic and x-ray crystallography measurements to study the thermodynamics associated with the decomposition of HCN2(SPh)3 by free radicals. Results show that the major products of the decomposition process are diazene and PhSSPh. The data also suggest that diazene is formed by a mechanism in which the RS radical acts as the catalyst.

Two ruthenium mononitrosyl porphyrins (TPP)Ru(NO)(H2O) BF4 and (TPP)Ru(NO)(ONO) where TPP was the dianion of 5,10,15,20-tetraphenylporphyrin, were synthesized, characterized, and studied by spectroscopic and electrochemical analyses. The crystal structure of (TPP)Ru(NO)(ONO) showed nitrosyl and O-bound groups in the axial and trans location to each other. The two complexes were irreversibly reduced at the metal center as the axial ligand trans dissociated to NO.

The synthesis of tellurium diimide dimers of the type RNTe(micro-NR')eTNR is presented. The scheme involves the reactions of the PN2Te heterocycle Ph2PN(SiMe3)2Te(Cl)NR (R= PPh2NSiMe3) with R'NHLi (R = tBu, tOct) and TeCl4 with tBuNHLi in a 1:4 molar ratio. Structural studies showed that the crystals of these dimers consist of a four-membered Te2Ne2 ring with the short, exocyclic Te=NR bonds arranged in either a cis or trans configuration.

A method of preparation for the soluble and insoluble alkali metal derivatives of the Ph4P2N4S2 dianion is the reduction of 1,5-Ph4P2N4S2 by M(BEt3H) in THF. These alkali metal derivatives can be used in the synthesis of organic derivatives and the metal complexes of the P2N4S2 ring. Ph4P2N4S2 dianion is a very strong reducing agent. The lithium and sodium derivatives of the dianion are insoluble, yellow powders. The bonding mode of the ligands are automatically adjusted to satisfy the electronic demands of transition metals.

Multinuclear NMR spectroscopy helps characterize lithium iodide adducts, prepared by a reaction of organic iodides with lithium reagents. These adducts upon dissolution in CH2Cl2 produce eight-membered rings with boat conformation. Heating leads to the formation of chair conformers from boat conformers. Synthesis of N-methylated adduct involves the reaction of methyl triflate with Ph4P2N4(SPh)2.

Metallocene dihalides MCp2Cl2 (M = Ti, Zr, Hf) react with (Li(Ph4P2N4S2R)THF)2 (R = Me, tBu, Ph, CH2PPh2) to produce complexes of the type MCp2Cl(Ph4P2N4S2R). X-ray analysis shows an eta(super 2)-N,S type of bonding of the (Ph4P2N4S2R)(super -) anion to the metal. This type of zirconium complex reacts with various electrophiles to produce regiospecific functionalized P2N4S2 ring. Spectroscopic techniques and x-ray analysis show this complex as a hydrogen-bonded dimer.

Synthetic tridentate nitrogen ligands, 2,9-disubstituted phen and pyrazolyl groups, coordinate with nickel(II)chloride hexahydrate to form five- and six-coordinate nickel(II) complexes. Three-dimensional X-ray diffraction methods help in structural characterization and cyclic voltammetry analyzes the redox properties of these compounds. Significant structural changes are observed during transition from one oxidation state to another.