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A five step synthesis of 8,16-dicyano-anti-[2.2]metacyclophane -1,9-diene from 1,3-bis(bromomethyl)benzonitrile is demonstrated.

The theoretical and crystallographic methods were used to investigate the two types of halogen...halide synthons. The findings have suggested that halogen...halide interactions are controlled by electrostatics and are characterized by linear C-Y...[X.sup.-] angles and separation distances less than the sum of van der Waals radius of the halogen atom and the ionic radii of the halide anion.

Two fluorine-containing bix (Fbix) ligands 2,3,5,6-tetrafluoro-1,4-bis(imidazol-1-yl-methyl)benzene and 2,3,5,6-tetrafluoro-1,4-bis(2-methylimidazol-1-yl-methyl)benzene were reported. The resultant non-interpenetration polymeric complexes formed by coordination of these ligands with metal salts, AgNO3, Co(ClO4)2.6H2O, Cd(NO3)2.4H2O, are reported as well as their solid-state structures.

A hemilabile pyrazolyl-functionalised N-heterocyclic carbene complex of palladium(II) is synthesized. It is an excellent catalyst for Heck and Suzuki cross-coupling reactions in ionic liquids.

The formation, structural, thermal and thermodynamic properties of the first quaternary salts of 4,4'-bi(1,2,4-triazole) or N-4-(1,2,4-triazole)-N-3-(4-methyl-1,2,4-triazole)amine by reaction with nitric or perchloric acid or 5-nitro-tetrazole are described. The melting points, thermal degradation temperatures and the standard heats of formation for compounds with perchlorate as the anion are found to be higher than those of the analogous nitrates, whereas the highest heats of formation are obtained when 5-nitro-tetrazolate is used as the energetic anion.

Energetic salts comprising substituted imidazolium and 1,2,4-triazolium cations and 4,5-dintro imidazolate and 5-nitrotetrazolate anions are synthesized and characterized. It is found that the imidazolate salts are denser but have lower heats of formation than their tetrazolate analogues.

Cyclic and acyclic guanidinium-based salts are synthesized with the help of the quarternization of guanidine derivatives with nitric or perchloric acid or with iodomethane followed by metathesis reaction with silver nitrate, silver perchlorate, or ammonium dinitroamide. Most of the salts exhibited low melting points and good thermal stabilities.

Research has been conducted on 1,2,4-triazole. The alkylation of this compound has been carried out, and the results demonstrate that the produced 1-alkyl triazoles have been quaternized via the use of fluorinated alkyl halides under neat reaction conditions.

Calculation of nucleus-independent chemical shift (NICS) values was done at several locations for a series of dimethyldihydropyrenes (DDPs). The NICS and experimentally determined relative aromaticities of the dimethyldihydropyrenes are in complete agreement, verifying that NICS can be used not only to classify a compound as aromatic but also to determine the degrees of aromaticity of structurally related systems.

Results discuss the reactions of alkyl, aryl, and mixed glyoxal hydrates with Deoxofluor leading to the formation of a mixture of meso and racemic polyfluoro- ethers. A mixture of two different glyoxal hydrates reacting with Deoxofluor yield mixed polyfluoroethers. Further, at low concentrations of glyoxal hydrates, difluoroaldehydes or tetrafluoro derivatives are formed.

Research has been conducted on the 2-methyl-2-(1',1',2',2',3',3',4',4'-nonafluoroheptyloxymethyl)-1,3-propanediol. The single-crystal X-ray structure of this compound has been investigated and the details are reported.

Research has been conducted on the design of the low dimensional coordination polymers containing Cu(I) and Cu(II) halides. The reaction of the copper(II) halides with 2,3-dimethylquinoxaline has been examined in obtaining the systems analogous to the pyrazine complexes but with the additional bulk of the dmq ligand and the results are presented.

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.

The reinvestigation of the molecular structure of the parent molecule N(sub 4)P(sub 4)F(sub 8) by using x-ray diffraction, gas electron diffraction and differential scanning calorimetry is described. The results from each of these measurements support a nonplanar eight-membered ring for N(sub 4)P(sub 4)F(sub 8) that is puckered and that undergoes a phase transition at -74 degrees C.

Syntheses of 1,3-ansa, spiro and bridged derivatives of tetrameric fluorophosphazene are discussed. In the presence of CsF, the ansa and bridged derivatives are converted to the spiro compound, indicating the higher thermodynamic stability of the latter.

Results reveal that gamma-ketoesters and gamma-diketones serve as precursors to both mono(trifluoromethyl)alcohols and bis(trifluoromethyl)diols as indicated by the cesium fluoride catalyzed trifluoromethylation of various alpha,beta and gamma diketo compounds with (trifluoromethyl)trimethylsilane. The yields of monoaddition and diaddition products are 70-75% and 5-10%, respectively.

Several m-terphenyl stabilized germylyne transition metal complexes and related metallogermylenes were synthesized and characterized.

A study was conducted to examine the use of transition-metal hydride complexes that could be generated by the heterolytic cleavage of [H.sub.2] gas to form B-H bonds. The results suggested that it is possible to form B-H bonds from B-X bonds, and the extent to which B[X.sub.3] compounds are reduced by transition-metal hydride complexes forming species containing multiple B-H bonds depends on the heterolytic B-X bond energy.

The synthesis, and structural and magnetic characterization of three [Cu.sup.2+]-containing coordination polymers, [Cu(H[F.sub.2])[(pyrazine).sub.2]]Sb[F.sub.6], [[Cu.sub.2]F(HF)(H[F.sub.2])[(pyrazine).sub.4]][(Sb[F.sub.6]).sub.2], and [CuAg([H.sub.3][F.sub.4])[(pyrazine).sub.5]][(Sb[F.sub.6]).sub.2] are presented. The polymers are found to crystallize in either tetragonal or orthorhombic space groups, have structures consisting of 2D square layers of [[M[(pyz).sub.2]].sup.n+] that are linked in the third dimension by either H[F.sub.2.sup.-] or [H.sub.3][F.sub.4.sup.-] and the variations observed in magnetic behaviors are driven by differences in the H***F hydrogen-bonding motifs.

The mixed-ligand complex [Ni(dppp)([P.sub.2.sup.Ph][N.sub.2.sup.Bz])][(B[F.sub.4]).sub.2] (where )([P.sub.2.sup.Ph][N.sub.2.sup.Bz] is 1,5-dibenzyl-3,7-diphenyl-1,5-diaza-3,7-diphosphacyclooctane and dppp is 1,3-bis(diphenylphosphino)propane) is prepared and its treatment with [H.sub.2] and triethylamine has resulted in the formation of [Ni.sup.0] complex. The mixed-ligand complex is a catalyst for the electrochemical oxidation of [H.sub.2] in the presence of base and new insights are presented for the mechanism derived from low-temperature NMR and thermodynamic studies.

The reactivity of the S-H bond in Cp*Mo[([mu]-S).sub.2]([mu]-SH)MoCp* ([S.sub.4]MeH) is analyzed by determining the kinetics of hydrogen atom abstraction to form the radical Cp*Mo[([mu]-S).sub.3]([mu]-SMe)MoCp* ([S.sub.4]Me), as well as reaction of hydrogen with the radical-dimer equilibrium to reform the S-H complex. The results have provided evidence for a radical addition/elimination pathway at an [Mn.sub.2][S.sub.4] core.

The crystal structures of [[[(n-[C.sub.4][H.sub.9]).sub.2]].sub.2][Cd.sub.9][Cl.sub.20].2[H.sub.2]O and [[Cu([C.sub.14][H.sub.24][N.sub.4])].sub.2][Cu.sub.13][Cl.sub.30][([H.sub.2]O).sub.2].x[H.sub.2]O compounds, containing perforated layer structures are studied. The water molecules are found to be hydrogen bonded to chloride ions on both sides of excision.

The reaction of [[N[Et.sub.4]].sub.2][Re[Br.sub.3][(CO).sub.3]] with 2,4-pentanedione (acac) has produced a complex of the type fac-Re(acac)([O[H.sub.2])[(CO).sub.3] under aqueous conditions. Acac is used as a bidentate ligand system in a '2+1' approach, which has the potential for linking to targeting molecules for generating in situ tridentate complexes for nuclear medicine applications.

The rapid and reversible reaction taking place between [Ni[([P.sup.cy][N.sub.2.sup.Bz]).sub.2]][(BF4).sub.2] complex and carbon monoxide is discussed. The second coordination sphere of the molecule is found to be essential for controlling the reactivity.

The synthesis and characterization of a series of heterocycle-based energetic salts from [[[O.sub.2]NC[(CN).sub.2]].sup.-] and [[[([O.sub.2]N).sub.2]C(CN)].sup.-] is reported. The densities and standard enthalpies of formation for these energetic salts are calculated, which have shown that all the salts possess higher enthalpies of formation than the nitrate analogues.

The room-temperature crystal structure of Dimethylammonium trichlorocuprate consisting of a linear chain of [Cu.sup.2+] dimers with unusual magnetic properties is presented. The reported structure has solved the confusion regarding the origins of the magnetic behavior of the compound and gives a convincing example of the importance of two-halide magnetic exchange.

A series of both imidazolium- and triazolium-based unsymmetric dicationic salts with alkyl and polyfluoroalkyl substituents are synthesized and characterized. The preliminary results of palladium-catalyzed Heck cross-coupling reactions have shown that the unsymmetric dicationic ionic liquids are a suitable solvent for cross-coupling reactions.

Demonstration showing that DFT calculations using the B3LYP/6-31G* method can satisfactorily predict the lowest energy conformers of a dithia[7]metacyclophane is presented. Detailed comparison of calculated and experimental proton and carbon chemical shifts, bond distances and angles and activation barriers verify that the calculations perform well in such cyclophane with a limited number of conformers.

Synthesis of new energetic salts (2, 3, 5, 6, 13, 14, 21, 22) was done via the quaternization of derivatives of N-aminoazoles with nitric or perchloric acid or with iodomethane followed by metathesis reaction with silver nitrate or silver perchlorate. Single-crystal X-ray analysis confirmed the structure of 2-amino-4,5-dimethyltetrazolium nitrate (21).

The straightforward syntheses of ferrocene-containing salts including the first room-temperature ionic liquids with ferrocenylmethyl-substituted cations are reported. The high-yield syntheses of the first mono- and disubstituted (ferrocenylmethyl)imidazolium and (Ferrocenylmethyl)-1,2,4-triazolium ionic liquids with T(sub g) values below 25 degree Celsius resulted from metathesis with methyl iodide quarternized ferrocene diazles and triazoles.

The investigation of two compounds that are obtained by synthesis of azide complexes with the copper(II) macrocycle complex Cu(14ane)(super 2+) which attempts to prepare chain systems based on azido linked copper(II) macrocycle complexes are reported. Magnetic studies reveal the presence of ferromagnetic interactions within the chains.

An efficient procedure for the syntheses of a family of new perfluoroalkyl-containing triazolium quaternary salts is developed. The results revealed that when there is a longer fluoroalkyl substituent at N-3, the variation of melting points is found to be greater, after metathesis with other salts.

Information about the dominant inorganic features in N-alkyldiammonium salts of copper (I) bromide is given. The diammonium cations hydrogen bond anionic (CuBr2)nn- chains together into a unique double layer structure.