Platinum Pt Cl

The observed red-shift is ascribed to the enhanced delocahzation of the excited Pt(Ill)-Pt(III) states in the coordination chain, which decreases the LUMO-HOMO energy gap of the one-dimensional complex. In the lipid complexes, densely packed sulfonate groups seem to direct the electrostatically bound Pt(en)2 and PtCl2(en)2 complexes to coordinate in higher density. This causes the increase in the overlap between dz2 and p orbitals, depending on the molecular packing and chemical structure of the lipid molecules. The shortened inter-platinum (Pt -Cl-Pt ) distance would pro-... 

Several methods are employed for the purification of the single platinum metal salts, for instance re-crystallization of Na2[Pt(Cl)6] with oxidative hydrolysis of the impurities of Pd, Rh, Ir, etc. which together with base-heavy metals are removed as insoluble hydroxides. Generally the metals are obtained, initially as sponge or powder, by conversion of their salts through thermal decomposition or by reduction of aqueous solutions of the ammonium-chloro complexes. Os which has been oxidized to the volatile 0s04 and Ru have to be reduced by H2. 

Platinum-diphosphine complexes in [C4CiIm][PPg] have been studied via ip NMR [67,68]. Here, the insertion reaction of SnClj into the Pt-Cl bond of PtCljCbdpp) was observed, as well as the formation of an additional cationic complex. The structure of the catalyst could be elucidated via characteristic Jpp and Jpt p coupling constants. 

Chloro-triammino-platinous Chloride, [Pt(NH3)3Cl]Cl, may be obtained by the addition of ammonia to dichloro-diammino-platinum, [Pt(NH3)2Cl2], or by the elimination of ammonia from tetrammino-platinous chloride by the action of hydrochloric acid thus ... 

In the annnino-platinous compounds there is, as in the other amniino-metallic compounds, a complete transition series from tetrammino-platinous salt to tetra-acido-platinous salt for example, tetrammino-platinous chloride, [Pt(NH3)JC12, chloro-triammino-platinous chloride, [Pt(NH3)3Cl]Cl, dichloro-diammino-platinum, [Pt(NH3)2Cl2], trichloro-ammino-platinous salt, [Pt(NH3)Cl3]K, and potassium chloropiatinite, [PtCl6]K2, where all the ammonia is replaced by chlorine. Comparing the molecular conductivities, the first-mentioned compound has conductivity at 1000 litres dilution of 260, the next 115-8 in the third compound the conductivity drops almost to zero, the fourth has conductivity of 106-8, and the last salt has conductivity of 267.2... 

When CO is passed through a suspension of K2PtCl4 in concentrated HC1 the initial carbonyl species formed is [Pt(CO)Cl3]-. Continued reaction leads to the platinum(I) carbonyl complex [Pt2(CO)2Cl ]2-. The structure shows two PtCl2(CO)- groups linked by a short Pt—Pt bond of 2.584(2) A.309 The long Pt—Cl bond lengths indicate a large trans influence for the Pt1—Pt bond. 

Carbon-bonded [-diketonate ligands, in which the metal is bonded to the central carbon, i.e. that flanked by two acetyl groups, are rather common in palladium and platinum chemistry and were first demonstrated in K[Pt(Cl)(C-MeC0CHC0Me)(0,0-MeC0CHC0Me)] (Figure 4).54... 

Treatment of K[Pt(0,O-MeCOCHCOMe)(C-MeCOCHCOMe)X] with mineral acids affords a material, formulated as Pt(0, -MeCOCHCOMe)Cl(MeCOCH2COMe) in which neutral, enolic acetylacetone is rc-bonded to platinum via the C=C bond. On standing, solutions of this material in chloroform yield red [Pt( -Cl)(MeCOCHCOMe)] . Similar acidification of K[Pt(MeCOCHC-OMe)3] with HX (X = Cl, Br) yields Pt(l,3,5,7-tetramethyl-2,6,9-oxabicyclo[3.3.1]nona-3,7-diene)2X2,248 whereas sulfuric, phosphoric or nitric acid leads to polymeric [Pt(MeCOCHCOMe)2]. This compound, which is isomeric with the familiar Pt(0,O-MeC0CHCOMe)2, may aggregate by means of tridentate C,0,0-MeCOCHCOMe bridging ligands.244... 

The bond length between platinum and the phospha-alkene is only 2.193 8 which is much shorter than the Pt-PEt3 bond (2.255 ) and is only slightly longer than the shortest known Pt-P distance (to PF3 2.141 ) in cis-PtCl2(PF3)(PEt3). Clearly the s-character of the phospha-alkene lone pair is significantly enhanced. These results and a discussion of their relationship with Pt-Cl distances and jp will be the subject of future papers. 

As mechanistic hypothesis it was proposed (9-11) that the excited platinum complex undergoes homolytic Pt Cl cleavage affording a Ptm intermediate and an adsorbed chlorine atom (Scheme 1), by analogy with the known photochemistry of hexachloroplatinate in homogeneous solution (23,31). Electron injection from the platinum(III) complex into the titania conduction band reforms PtIv. Thus, the... 

Another Ptm dimer unsupported by covalent bridges has been reported and structurally characterized by X-ray crystallography [50]. Each platinum unit carries two l,2-(cyclooctane)dioximate ligands and is capped by chloride ligands. Structural features are very similar to those found for the previous three species a part from slightly shorter Pt-Cl axial bonds (mean value of 2.40 A as compared with a mean value of 2.46 A of the previous compounds) which reveals that also axial ligands can be very sensitive to steric interactions with the equatorial ligands. 

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