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The molecular and supramolecular features of three triangular copper(II) propionate secondary building units (SBUs) which form different, self-assembled, 3D metal-organic frameworks (MOFs) are reported. The compounds are remarkably active and selective catalysts or catalyst precursors for the mild peroxidative oxidation of cycloalkanes under mild conditions, into the corresponding alcohols and ketones.

The syntheses of mixed-ligand tetranuclear gold(I) complexes, which result from the reaction of less bulky amidinates and pyrazolates with the bulky ligand dinuclear [[Au.sub.2](2,6-[Me.sub.2]Ph-form).sub.2] is described. It is found that the steric effect of the bulky ligands can block the formation of the tetranuclear species allowing for isolation of the dinuclear and trinuclear complexes.

Different polycatenar pyrazole ligands (Ln) was used to prepare several new cis-[RhCl[(CO).sub.2](Ln)] complexes and obtain columnar liquid crystalline arrangements. The topology of the ligand plays an essential role to induce mesophase at room temperature from a nonmesogenic pyrazole only when it is symmetrically substituted with six decyloxy chains.

The structural features and thermal properties of a series of 3,5'-di-tert-butylpyrazolates as the donor-free oligonuclear and the donor-containing dinuclear species were compared to understand the role of donors and secondary interactions. A comparison of the volatility and thermal stability of the heteroleptic, dinuclear pyrazolate complexes with homoleptic oligonuclear complexes suggests that the presence of ethereal neutral donors might promote decomposition through close contacts but further studies are needed to support this view.

The preparation and structural characterization of silver(I) complexes of the arene-linked bis(pyrazolyl)methane ligands m-[[CH[(pz).sub.2]].sub.2][C.sub.6.][H.sub.4], ( and p-[[CH[(pz).sub.2]].sub.2][C.sub.6.][H.sub.4] and 1,3,5-[[CH[(pz).sub.2]].sub.3]C.sub.6.][H.sub.3] is described. The findings reveal that use of the tritopic ligand affords stoichiometry-dependent complexes containing either discrete dimeric metallacycles with equimolar amounts of silver salts and ligand or a polymer of metallacycles in the presence of an excess of silver salt.

The representative of P,P,P-trichloroylides-5-methyl-2-phenyl-4-(trichlorophosphoranylidene)2,4-dihydro-3H-pyrazol-3-one was synthesized and characterized. Some chemical properties were studied and compared with one of P,P,P-trichloroylides-5-methyl-2-phenyl-4-(trichlorophosphoranylidene)2,4-dihydro-3H-pyrazol-3-one.

Second-order degenerate perturbation theory, in conjunction with the group homomorphism method for describing a similarity transformation, are used to characterize the subspace of two-state conical intersections contained in the branching space of a three-state conical intersection. It is shown by explicit calculation, using the lowest three-state conical intersection of (CH)3N2, that a second-order treatment yields highly accurate absolute energies, even as significant distances from the references point of three-state intersection.

The synthesis of mixed-metal trinuclear gold-silver complexes by the direct reaction of gold(I) carbeniate and gold(I) benzylimidazolate with silver(I) pyrazolate complex is described. This presents a new approach to cluster mixed-metal synthesis with potential use in mixed-metal catalysis.

The magnetic properties of all complexes were studied by variable-temperature magnetic susceptibility and magnetization measurements. The obtained parameters of J range from -33.1 to -211 cm(super -1), indicating very strong antiferromagnetic coupling between Cu(super II) ions.

A series of nanosized cavity-containing bipyrazolate-bridge metallomacrocycles with dimetal centers are synthesized through a directed self-assembly approach involving spontaneous deprotonation of the 1H-bipyrazolyl ligands in aqueous solution. The complexes have weak Pd(II)...Pd(II) or Pt(II)...Pt(II) interactions are characterized by elemental analysis (super 1)H and (super 13)C, NMR, cold-spray ionization or electrospray ionization mass spectrometry, UV-visible spectroscopy and luminesescence spectroscopy.

Rh(III) diketonate complexes of formula [Cp*M(Q)Cl] (M=Rh or Ir, Cp*=pentamethylcyclopentadienyl, HQ=1-phenyl-3-mthyl-4R(C=O)-pyrazol-5-one) is easily synthesized by reaction of [Cp*MCl2]2 with the adequate sodium salt NaQ. [Cp*M(Q)Cl] complexes exist as enantiomers, both in the solid state and in solution, the mental being a center of chirality. The [Cp*M(Q)Cl] complexes are stable in solid state and in the atmosphere for a long time, and they are also stable in weak polar solvents and up to 55 degree Celsius.

The crystal structure of [Cu(Npy2pz)]2(ClO4)2.2CH3CN is determined by x-ray crystallography and it is found to consist of two nearly identical discrete dinucler molecules with bis(pyrazolato) bridges. Variable temperature-dependent magnetic data shows that antiferromagnetic interactions operate in [Cu(Npy2pz)]2(ClO4)2.2CH3CN as a result of the binding angle of the pyrazolato bridge.

A series of heteroleptic Ir(III) metal complexes bearing two N-phenyl-substituted pyrazoles and one 2-pyridyl pyrazole ligands are synthesized and characterized to attain highly efficient, room temperature blue phosphorescence. The results on the basis of steady-state, relaxation dynamics, and theoretical approaches, lead to a conclusion that the weakening of iridium metal-ligand bonding strength in the T1 state plays a crucial role for the fast radiationless deactivation.

A novel one-step synthesis route to fully substituted pyrazol-4-ols is reported. This simple yet nonobvious method for the construction of pyrazol-4-ols by the condensation-fragmentation-cyclization-extrusion reactions of thietanones with 1,2,4,5-tetrazines is reported.

A practical and scalable pathway to selective CC[K.sub.1] receptor antagonist is described. The key features in the concise route include a regioselective construction of the pyrazole core through the reaction of an aryl hydrazine and an elaborated acetylenic ketone, a [Tf.sub.2]O/pyridine mediated Z-selective dehydration of an [alpha]-hydroxyester and a stereoselective hydrolysis.

The enantioselective catalysis of 1,3-dipolar cycloaddition reaction of nitrones with propioloylpyrazole and acryloylpyrazole derivatives in presence of a chiral copper(II) complex of 3-(2-naphthyl)-L-alanine amide is described. The reaction is the first successful method for the catalytic enantioselective 1,3-dipolar cycloaddition of nitrones with acetylene derivatives.

Two highly porous coordination polymers, containing rare octanuclear hydroxo-nickel clusters and long bis-pyrazolyl spacers are reported. The polymers are found to possess lattice cavities up to 72% of the total crystal volume after mild thermal treatment.

1,3-Dipolar cycloaddition reactions of VDCP-diesters with aromatic diazomethanes generated in situ from the aromatic aldehydes and tosylhydrazine mediated by base produce pyrazole derivatives under mild conditions. A plausible reaction mechanism is proposed based on the control experiments along with the discussion on the regioselectivity.

Several studies are conducted to explain the synthesis, characterization, as well as the properties of the various dinuclear Pt(II) 6-(5-t rifluoromethyl-p yrazol-3-yl)-2,2?-bipyridine complexes. The dual phosphorescence exhibited by these dinuclear complexes is also examined.

Catalytic CuI and sparteine have annulated 2-formylpyrroles with o-aminoiodoarenes to produce substituted pyrrolo[1,2-a]quinoxalines and related heterocycles. The reaction has worked for annulation of 2-formylindoles, 2-formylimidazole, 2-formylbenzimidazole and a 3-formylpyrazole.

The cycloaddition of 4-iodosydnones with terminal alkynes has proceeded with good regiocontrol in order to produce 5-iodo pyrazoles. These products have participated in subsequently C-C and C-heteroatom bond forming processes.

A facile and efficient Cu(I)-catalyzed cross-coupling method is described for preparing of N-alkynyl or N-bromoalkenyl heteroarenes from bromoalkynes. The studies have shown that poly(ethylene glycol) 400 (PEG400) has acted as both a Cu(I)-stabilizing ligand as well as a phase transfer solvent.

Detailed photophysical studies was performed on a series of Cu(I)-responsive fluorescent probes that are based on a 16-membered thiazacrown receptor ([16]aneNS3) tethered to 1,3,5-triarylpyrazoline-fluorophores to determine the possible involvement of Cu(I) in adverse quenching pathways. The combined photophysical, electrochemical, and solution chemistry experiments demonstrated that electron transfer from Cu(I) does not compete with radiative deactivation of the excited fluorophore, indicated that Cu(I)-induced fluorescence switching is kinetically controlled.

A short and straightforward synthesis of a series of pyrazolo[1,5-f]phenanthridine derivatives and regioselective synthesis of 1,5-diarylpyrazole intermediates are described. The scope and limitations of the two methodologies are explored to establish the complementariness of the reaction and also establish the environmentally safer porotcols for catalysts used.

A newly developed chelation-assisted palladium-catalyzed cascade bromination/cyanation reaction of 2-arylpyridine and 1-arylpyrazole C- H bonds is reported. The one-pot reaction which utilized [K.sub.3][Fe[(CN).sub.6]] as a safe and nontoxic cyanide source provide aromatic nitriles in moderate to good yields.

The studies related to the scope and limitation of the combined ruthenium-lipase induced dynamic kinetic resolution (DKR) through O-acetylation of racemic heteroaromatic secondary alcohols (1-heteroaryl substituted ethanols) are presented. The results obtained provide better understanding of the mechanistic aspects behind the difference in reactivity of 1-heteroaryl substituted ethanols in comparison to reference substrates.

Several studies are conducted to explain the derivation of allenes taking place via the aromaticity observed in 3,5-bis([pi]-donor) substituted pyrazolium ions. The strength of the donor is shown to be directly related to the exocyclic delocalization occurring at this stage.

The efficient Suzuki cross-coupling of pyrazoline nonaflates with organoboron reagents was performed to obtain diverse 3-substituted-2-pyrazolines in excellent yield. The wide scope of the process could be used as a rapid, divergent strategy for the synthesis of elaborated 2-pyrazolines that are not readily available via conventional methods.

The addition of diazomethane and diazoethane to enantiopure (S)-(+)-3-[(methylphenyl)sulfinyl]-5,6-dihydropyran-2-one has produced the corresponding pyrazolines with almost complete [pi]-facial selectivity. The results are improved starting from sulfonyl pyrazolines, which has produced pure 3-oxabicyclo[4.1.0] heptan-2-ones.

The catalytic intermolecular C-H arylation of pyrazoles, namely SEM-protected pyrazoles with N-alkylpyrazoles, is described, which has helped in the synthesis of complex arylated pyrazoles. The catalytic C-H arylation combined with the protecting group transposition and N-alkylation has provided a rapid route for fully substituted pyrazoles with complete regiocontrol of all substituents.

An intramolecular 1,3-dipolar cycloaddition method is used for an efficient synthesis of the benzofuropyrazole skeleton. The method could be used to prepare a wide range of pharmaceutically active benzofuropyrazoles by using Pd-catalyzed coupling strategies.