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Research has been conducted on the macrocyclic oxamide's lanthanide(III)-copper(II) complexes. The synthesis and characterization of these complexes have been carried out via the use of IR, elemental analysis and electronic spectra and the details are reported.

A highly enantioselective Morita-Baylis-Hillman (MBH) reaction of isatins and acrolein is described that has provided enantiomerically enriched 3-substituted 3-hydroxyoxindoles, which has served as valuable synthetic building blocks. HatakeyamaEs catalyst, [beta]-isocupreidine, is shown to be a powerful catalyst for this transformation.

A reversible in situ acidic catalytic system comprising recyclable TEMPO functionalized imidazolium salt ([Imim-TEMPO][Cl]/NaN[O.sub.2]/C[O.sub.2]/[H.sub.2]O is developed for selective transformation of a series of aliphatic, allylic, heterocyclic and benzylic alcohols to the respective carbonyl compounds. The system has avoided any conventional acid, has eliminated unwanted byproducts and has provided a safe environment for oxidation involving oxygen gas.

Research has been conducted on building block [Cu(oxbe)] (super)-. Results demonstrate that the self-assembly of this building block with Mn(II) leads to coordinationpolymer {[Cu(oxbe)]Mn(H (sub)2 O)[Cu(oxbe)(DMF)]} (sub)n .nDMF.nH (sub)2 O.

To promote the application of polyacrylamide (PAM) in carbon dioxide flooding to enhance oil recovery, the solubility of PAM with different molecular weight (5 million, 7 million, 14 million, g·mol-1) was measured using dynamic method in supercritical carbon dioxide (SCCO2) at temperatures of 313, 323, and 333 K and pressures from 9.0 to 18.0 MPa. By comparing the differences of solubility data measured in SCCO2, the effects of pressure, temperature and molecular weight on the solubility of PAM in SCCO2 were investigated. The solubility data of PAM in SCCO2 was correlated with five density-based semiempirical models (Chrastil, A-L, M-T, S-S, and Bartle) and A-L model obtained the best correlated results for PAM with different molecular weight. The self-consistency of PAM solubility was verified by M-T model. The enthalpy values of PAM, including ΔH t, ΔH vap, and ΔH solv, were estimated through Chrastil and Bartle models. [ABSTRACT FROM AUTHOR]

Two novel complexes, [{Mn(salen)}2{Mn(salen)(CH3OH)}{Cr(CN)6}]n·2nCH3CN·nCH3OH (1) and [Mn(5-Clsalmen)(CH3OH)(H2O)]2n[{Mn(5-Clsalmen)(μ-CN)}Cr(CN)5]n·5.5nH2O (2) (salen2- = N,N′-ethylene-bis(salicylideneiminato) dianion; 5-Clsalmen2- = N,N′-(1-methylethylene)-bis(5-chlorosalicylideneiminato) dianion), were synthesized and structurally characterized by X-ray single-crystal diffraction. The structural analyses show that complex 1 consists of one-dimensional (1D) alternating chains formed by the [{Cr(CN)6}{Mn(salen)}4{Mn(salen)(CH3OH)}2]3+ heptanuclear cations and [Cr(CN)6]3- anions. While in complex 2, the hexacyanochromate(III) anion acts as a bis-monodentate ligand through two trans-cyano groups to bridge two [Mn(5-Clsalmen)]+ cations to form a straight chain. The magnetic analysis indicates that complex 1 shows three-dimensional (3D) antiferromagnetic ordering with the Neel temperature of 5.0 K, and it is a metamagnet displaying antiferromagnetic to ferromagnetic transition at a critical field of about 2.6 kOe at 2 K. Complex 2 behaves as a molecular magnet with Tc = 3.0 K. [ABSTRACT FROM AUTHOR]

Three Ru[sup5+],[sub2] diruthenium complexes, (4,0) Ru[sub2](2-CH[sub3]ap)[sub4]Cl, (3,1) Ru[sub2](2-Fap)[sub4]Cl, and (3,1) Ru[sub2](2,4,6-F[sub3]ap)[sub4]Cl where ap is the 2-anilinopyridinate anion, were examined as to their electrochemical and spectroelectrochemical properties in five different nonaqueous solvents (CH[sub2]Cl[sub2], THF, PhCN, DMF, and DMSO). Each compound undergoes a single one-electron metal-centered oxidation in THF, DMF, and DMSO and two one-electron metal-centered oxidations in CH[sub2]Cl[sub2] and PhCN. The three diruthenium complexes also undergo two reductions in each solvent except for CH[sub2]Cl[sub2], and these electrode processes are assigned as Ru[sup5+/4+],[sub2] and Ru[sup4+/3+],[sub2]. Each neutral, singly reduced, and singly oxidized species was characterized by UV-vis thin-layer spectroelectrochemistry, and the data are discussed in terms of the most probable electronic configuration of the compound in solution. The three neutral complexes contain three unpaired electrons as indicated by magnetic susceptibility measurements using the Evans method (3.91 -3.95 μ[subB]), and the electronic configuration is assigned as σ[sup2]π[sup4]δ[sup2]π[sup*2]δ independent of the solvent. The three singly oxidized compounds have two unpaired electrons in CD[sub2]Cl[sub2], DMSO-d[sub6], or CD[sub3]CN (2.65-3.03 μ[subB]), and the electronic configuration is here assigned as σ[sup2]π[sup4]δ[sup2]π[sub*2]. The singly reduced compound also has two unpaired electrons (2.70-2.80 μ[subB]) in all three solvents, consistent with the electronic configuration σ[sup2]π[sup4]δ[sup2]π[sup*2]δ[sup*2] or σ[sup2]π[sup4]δ[sup2]π[sup*3]δ[sup*]. Finally, the overall effect of solvent on the number of observed redox processes is discussed in terms of solvent binding, and several formation constants were calculated. [ABSTRACT FROM AUTHOR]

Factors affecting the electrochemical and spectroelectrochemical properties of diruthenium(III,II) complexes containing four unsymmetrical bridging ligands are reported for seven related compounds which were isolated in one or two of the four possible isomeric forms. The investigated compounds are represented as Ru[sub 2](2-CH[sub 3]ap)[sub 4]Cl, Ru[sub 2](2,5F[sub 2]ap)[sub 4]Cl, Ru[sub 2](2,6-F[sub 2]ap)[sub 4]Cl, and Ru[sub 2](2,4,6-F[sub 3]ap)[sub 4]Cl where 2-CH[sub 3]ap, 2,5-F[sub 2]ap, 2,6-F[sub 2]ap, and 2,4,6-F[sub 3]ap are, respectively, the 2-(2-methytanilino)pyridinate anion, the 2-(2,5-difluoroanilino)pyridinate anion, the 2-(2,6-difluoroanilino)pyridinate anion, and the 2-(2,4,6-trifluoroanilino)pyridinate anion. Ru[sub 2](2-CH[sub 3]ap)[sub 4]Cl and Ru[sub 2](2,5-F[sub 2]ap)[sub 4]Cl exist only in a (4,0) conformation while Ru[sub 2](2,4,6-F[sub 3]ap)[sub 4]Cl is present in both (3,1) and (4,0) isomeric forms. Ru[sub 2](2,6F[sub 2]ap)[sub 4]Cl also exists in two isomeric forms, but only the (3,1) isomer was generated in sufficient quantities to be isolated and structurally characterized. This series of seven closely related metal-metal bonded complexes thus provides the first possibility to systematically examine how differences in position and number of the electrondonating or electron-withdrawing groups on the anionic bridging ligands might be related to the electronic properties and structural features of the compound as well as the type and number of geometric isomers which are formed. Each diruthenium derivative undergoes three one-electron transfers in CH[sub 2]Cl[sub 2] containing 0.1 M tetra-n-butylammonium perchlorate (TBAP). The first reduction and first oxidation products were characterized by thin-layer UV-vis spectroelectrochemistry, and the spectroscopic data, along with E½ values, were then related via linear free energy relationships to the type of isomer and/or position of the electron-donating or electron-withdrawing... [ABSTRACT FROM AUTHOR]

A reversible in Situ acidic catalytic system comprising recyclable TEMPO functionalized imidazolium salt ([lmim-TEMPO][Cl])/NaNO2/CO2/H2O was developed for selective transformation of a series of aliphatic, allylic, heterocycic, and benzylic alcohols to the respective carbonyl compounds. Notably, the system avoids any conventional acid and can eliminate unwanted byproducts, facilitate reaction, ease separation of the catalyst and product, and also provide a safe environment for oxidation involving oxygen gas. [ABSTRACT FROM AUTHOR]