Silver complexes dimethylformamide

The use of ISEs in non-aqueous media(for a survey see [125,128]) is limited to electrodes with solid or glassy membranes. Even here there are further limitations connected with membrane material dissolution as a result of complexation by the solvent and damage to the membrane matrix or to the cement between the membrane and the electrode body. Silver halide electrodes have been used in methanol, ethanol, n-propanol, /so-propanol and other aliphatic alcohols, dimethylformamide, acetic acid and mixtures with water [40, 81, 121, 128]. The slope of the ISE potential dependence on the logarithm of the activity decreases with decreasing dielectric constant of the medium. With the fluoride ISE, the theoretical slope was found in ethanol-water mixtures [95] and in dimethylsulphoxide [23], and with PbS ISE in alcohols, their mixtures with water, dioxan and dimethylsulphoxide [134]. The standard Gibbs energies for the transfer of ions from water into these media were also determined [27, 30] using ISEs in non-aqueous media. 

For their formal synthesis of (5E,9Z)-(+)-indolizidine 223AB ent 1780), Sulikowski and his team devised an interesting intramolecular Heck cyclization of the enamide 1791, which was promoted by a palladiu-m(II)-(R)-BINAP complex with silver phosphate as haHde scavenger (Scheme 226). When performed in dimethylformamide as solvent, the reaction produced the (R)-(+)-8,8a-dihydroindoUzin-3(7H)-one 1792 in 64% yield and an ee of 85%. Reduction of the conjugated alkene followed by treatment with methanol in trifluoroacetic acid produced the... 

There are many examples of the synthesis of homoleptic solvento-complexes by halide abstraction from compounds containing both coordinated halides and solvento-ligands. Palladium chloride is known to dissolve in nitriles, dimethylformamide, and dimethyl sulfoxide with the formation of complexes of the type [PdCl2(solv)2] which can be isolated as solids.3 The reaction of [PdCl2(RCN)2] with an excess of silver ions s is a convenient method for the synthesis of [Pd(RCN)4]2+. The tetra(acetonitrile)-platinum(II) and tetra(propionitrile)platinum(II) salts have been prepared in this way (Scheme 4.6). Wayland and Schramm have synthesized homoleptic palladium(II) complexes with DMSO, DMF, and DMAA in a similar manner. 

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