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Three heterometallic Au-Pt complexes [Pt2(PPh3)4(mu-S)(mu3-S)Au(PPh3)][PF6], [Pt2(PPh3)4(mu3-S)2Au2(mu-dppm)][PF6]2 and [Pt2(PPh3)4(mu3-S)2Au2(mu-dppf)][PF6]2 are synthesized and characterized. All three complexes are fluxional in solution with different mechanisms.

A study was conducted to evaluate the efficiency of a one-pot system that can catalytically dehalogenate highly-chlorinated aroclors and benzenes at reasonable conversion rates. The system utilizes THF as solvent, PdCl2(dppf) as catalyst, NaBH4 as reducing agent and TMEDA as a supporting base. Results on dechlorination efficiency and regioselectivity were considered satisfactory.

The use of a carbon monoxide gas as a reducing and desulfurizing agent enabled forming metal-metal bonds in a conversion of a {M3S2} aggregate to a {M3S} cluster. This transformation establishes a synthetic relationship between {Pt2MS2} trigonal bipyramidal aggregates and {pt2MS} tetrahedral clusters. The process involves heterometalation, carbonylation and reductive desulfurization and provides a general approach to metal-metal bond formation and the synthesis of triangular heterometallic clusters of platinum.

Three optically pure P-chiral diphosphines were efficiently synthesized by the palladium-complex-promoted asymmetric Diels-Alder reaction of 1-phenyl-3,4-dimethylphosphate with diphenylvinylphosphine, (E)-diphenyl-1-propenylophosphine and (Z)-diphenyl-1-propenylophosphine, respectively. (S)-(1-(dimethyllamino)ethyl)naphthalene was used as the chiral auxilliary in the reaction. The diphosphines were observed to be highly air-sensitive in the free ligand and powerful sequesters of group 8 metals.

The basic hetereometallic ligand (Pt2{dppf}2{mu-S}2) (dppf = 1,1'-bis{diphenylphosphino}ferrocene) complexes with the Lewis acid TlNO3 to form an interpolymetallic complex (Pt2Tl{dppf}2{mu3-S}2). The product metathesizes with NH4PF6 to yield the PF(super -)(sub 6) salt. The side-on attachment of the ligand creates an empty space on the Tl atom in the product complex. The two dppf ligands are chemically equivalent. A two-electron-transfer process induces the oxidation of Tl+ to Tl3+.

Structural studies of (Ag2(OAc)2(dppm))2 (dppm = bis(diphenylphosphino)methane) reveal that the complex is tetranuclear in the solid state, while it is dinuclear in solution. Structural data reveal the ability of carboxylate diphosphine complexes to exhibit polymerization isomerism between solution and solid states. Addition of dppm to (Ag2(OAc)2(dppm))2 shifts the acetate ligands from bridging to chelating modes, generating an (Ag(OAc)(dppm))2 metallocycle.

Ferrocene-based diphosphine complexes are subjected to NMR conformational analysis to illustrate their fluxionalities. The phenyl rotations and the ferrocenyl mobilities allow the dppf ligand to have a suitable conformation between two metal centers. The metal environment has no influence in the conformation. The ligand adaptability stabilizes the dppf ligand with respect to dissociation.

The reaction of AgNO3 and 1.1-bis(diphenylphosphino)ferrocence (dppf) in a 2:1 molar ratio the forms (Ag(NO3)dppf) which, with addition of Na+X-, where X = CH3CO2, C6H5CO2 and HCO2, leads to the syntheses of the corresponding complexes. The complexes (Ag2(CH3CO2)2)(dppf)2, (Ag2(C6H5CO2)2(dppf)) and (Ag2(HCO2)2(dppf)3) showed distinct structures as shown by the X-ray crystallographic analysis. In addition, all the structures exhibit the adaptability of dppf in its coexistence with other ligands.

The reaction of Ph2PCH2CH2SMe with bis(mu-chloro)bis(R-1- dimethylamino ethyl naphthylenyl-C super 2,N)dipalladium(II) produced three diastereomers. These compounds are air-stable and crystalline and remain inert in the presence of common oxidizing agents. The thiophosphine complex consists of an equimolar mixture of two diastereomers, with four molecules per unit cell. One cation of Rc,Rs and two cations of Rc,Ss have been identified, with a fourth cation disordered about the S14 atom. The hexafluorophosphate anions are uncoordinated.

A systematic approach to designing a self-contained qualitative analysis test for transition metal compounds exists. The compounds are exciting for use in qualitative analysis (QA) tests for students because of color changes they can exhibit. Students can be tested to advantage on knowledge of these species and the metathesis and redox reactions with special tests. The approach makes it almost impossible to rely on one- or two-step deductions. Principles of QA still are the basis for the development of many automated analytical techniques, and learning QA helps students learn about chemical reactions.

The conversion of Pt2(PPh3)4(mu-S)2 to [Ag{Pt2(PPh3)4(mu-S)2]2+ via [AgPt2(PPh3)5(mu3-S)2]+ and Ag2Pt2Cl2(PPh3)4(mu3-S)2 was analzyed to characterize the sequential growth of heteropolymetallic sulfides. Analysis of the synthetic growth process indicated the presence of an aggregate growth mechanism that was characterized by the stepwise addition of Ag+ and the Pt2 metalloligand. Furthermore, the reaction was characterized by the suquential unfolding and folding of the {PT2S2} butterfly core.

Lewis acid-base reactions between Pt2(mu-S)2(PPh3)4 and GaCl3, InCl3 lead to the formation of ((PPh3)4Pt2(mu3-S)2GaCl2)(GaCl4). The cation-anion pair in the product results from chloride transfer. The other product formed, (PPh3)4Pt2(mu3-S)2InCl3 is an 1/1 adduct complex. This product has a square-based pyramidal structure with a 4-coordinated adduct of InX3.

The structure of heterometallic sulfide is determined by single-crystal X-ray diffraction. The supporting anions play an active role in the structural assembly process is explained. An unexpected disintegration complex [Pt(sub 2)(S2CH2)Cl(PPh3)(sub 4)][PF6] is isolated and characterized by single-crystal X-ray diffraction.

The construction of molecular entities with specific geometrical patterns is illustrated, which demonstrates that the (bi) thienyl entity can be retained or replaced depending on the conditions. The unusual features of the products are described.