A New One-Dimensional Platinum System Consisting of Carboxylate-Bridged cis-Diammineplatinum Dimers¹

Abstract

With the aim of developing new 1D platinum chain solids having infinite Pt-Pt bonds, several carboxylate-bridged cis-diammineplatinum dimers have been prepared and structurally characterized. For a dimer doubly bridged with acetates, five different salts [Pt 2 (NH 3 ) 4 (µ-CH 3 CO 2 ) 2 ]X 2 ‚nH 2 O (X 2 , n ) (ClO 4 ) 2 , 2, 1; (NO 3 ) 2 , 1, 2; (BF 4 ) 2 , 4, 3; (PF 6 ) 2 , 2, 4; (SiF 6 ), 4, 5) have been prepared. The crystal structure of 5 has revealed that an infinite dimer chain [Pt 2 (NH 3 ) 4 (µ-CH 3 CO 2 ) 2 ] n 2n+ can be given as a result of hydrogen bond formation between the ammines and the oxygen atoms of acetates, demonstrating our prediction that the N 2 O 2 coordination sphere may serve as a hydrogen-bonding moiety to assist formation of an infinite dimer chain. An asymmetric dimer bridged by both acetate and hydroxide ligands, [Pt 2 (NH 3 ) 4 (µ-CH 3 CO 2 )(µ-OH)](SiF 6 ) (6), has also been isolated as a byproduct of 5, and a similar 1D framework, [Pt 2 (NH 3 ) 4 (µ-CH 3 CO 2 )(µ-OH)] n 2n+ , has been characterized by X-ray diffraction. In addition, some glycolate-bridged analogues of similar frameworks have been synthesized and characterized: [Pt 2 (NH 3 ) 4 (µ-CH 2 (OH)CO 2 ) 2 ](SiF 6 )‚4H 2 O (7), [Pt 2 (NH 3 ) 4 (µ-CH 2 -(OH)CO 2 ) 2 ](ClO 4 ) 2 ‚H 2 O (8), and [Pt 2 (NH 3 ) 4 (µ-CH 2 (OH)CO 2 )(µ-OH)](NO 3

Luminescence Rigidochromism and Redox Chemistry of Pyrazolate-Bridged Binuclear Platinum(II) Diimine Complex Intercalated into Zirconium Phosphate Layers

“…25,35 Therefore, the binding energies for the major component are consistent with an oxidation state intermediate between Pt(II) and Pt(III). In support of this interpretation, we present the binding energies of amidate-bridged tetramers 23 Thus, the XPS data are consistent with disproportionation of the Pt dimer within the heterogeneous chemical microenvironment of ZrP. The blue-gray color of the intercalated material also is consistent with this suggestion, since a blue color is characteristic of partial oxidation of the metal centers of "platinum blues".…”

Acetate-Bridged Platinum(III) Complexes Derived from Cisplatin

“…Closed-shell d 8 –d 8 interactions most likely promote this close contact. 74–76 The structure of the previously reported SiF 6 2− salt of [ 1 ] 2+ also includes infinite stacking of platinum(II) dimer cations, 27 which rules out crystal packing as an explanation for the phenomenon.…”

“…27 At 4 °C the nitrate salt of this compound precipitates from aqueous solution as brown needles. The initial yield of the compound was only 13%.…”

DFT study of the role of intermolecular interactions in the formation of stable halogeno– and ammineaqua– platinum(II) coordination compounds

“…The origin of the large class of homo‐ and mixed‐valence di‐, tetra‐, octa‐, and linear‐chain platinum complexes, which includes carboxylato‐bridged cis ‐diammineplatinum dimers 1 and the family of the mixed‐valence platinum amidato‐bridged complexes (the so‐called “platinum blues” 2, 3), stems from [ cis ‐Pt(NH 3 ) 2 Cl 2 ] and [ cis ‐Pt(NH 3 ) 2 (H 2 O) 2 ] 2+ . In contrast to cis ‐isomers, trans ‐isomers have no tendency to form complexes with PtPt bonds.…”