52241-27-7

Upstream product

• 23858-10-8 cis-(ethylenediamine)diiodoplatinum(II) 
• 7732-18-5 water 
• 14096-51-6 dichloro(ethylenediamine)platinum(II) 

Downstream Products

• 23858-09-5 PtBr2(ethane-1,2-diamine) 

Relevant academic research and scientific papers

Discrete Molecular Squares {[(en)M(CN)]4}4+ Derived from [(en)M(CN)2] (M = PtII, PdII)

C2h-symmetrical tetranuclear metallacycles {[M(en)(CN)] 4}(NO3)4 with M = PdII (4) and PtII (5) have been prepared upon reacting M(en)(CN)2 [M = PdII (1), PtII (2)] with [M(en)(H2O) 2](NO3)2. Replacement of the nitrate anions of 5 by terephthalate anions yields the corresponding salt 5a. The X-ray crystal structures of 1, 4, 5, and 5a have been determined. In the metallacycles 4, 5, and 5a the four metals form almost ideal squares with average M···M distances of ca. 5.05 A? (5, 5a) and 5.08 A? (4) along the sides. As shown by 1H NMR spectroscopy, the Pt square 5 is stable in aqueous solution, whereas the Pd square 4 undergoes rearrangement reactions upon aging or the presence of other Pd species such as (bpy)PdII. Preliminary studies on the possibility of non-covalent interactions of 4 and 5 with model nucleobases in water reveal that only 5 is useful in this respect. According to the concentration-dependence 1H NMR study, there is an interaction with the purine base 9-ethyladenine, molecular details of which are unclear at this stage, however. Compound 4 is substitutionally labile and is transformed into the coordination compound 8 with 1-methylcytosine. Two more side products, produced during the various reactions carried out, were characterized by X-ray crystallography: [Pt(en) 2][Pt(CN)4] (3) and [Pd(bpy)(en)](SO4) ·3H2O (7). Cationic molecular squares composed of (en)M (M = PtII, PdII) corners and cyanide bridges have been prepared and details of their formation and reactivity have been studied. Copyright

Intramolecular competition between histidine and methionine side chains in reactions of dipeptides with [Pt(en)(H2O)2]2+ (en = H2NCH2CH2NH2)

The pH- and time-dependent reactions of [Pt(en)(H2O)2]2+ (en = H2NCH2CH2NH2) with the histidylmethionine dipeptides cyclo(-his-met-), his-Hmet and met-Hhis at 313 K have been studied by ion-pairing reversed-phase HPLC and 1H and 195Pt NMR spectroscopy. Quantitative formation of the unusually large 12-membered chelate ring in the remarkably inert complex [Pt(en){cyclo(-his-met-)}]2+ is complete within a few minutes. A base-catalysed configuration inversion for one of the diketopiperazine α-C atoms at pH > 9 leads to the observation of two well separated HPLC fractions for both the prevailing κ2N′met,S co-ordinated species and the peptide itself. An analogous likewise kinetically stable macrochelate is present after 14 d as a major species in the [Pt(en)(H2O)2]2+-his-Hmet reaction mixture over the whole range 3.2 a kinetically favoured κ2O,S chelate is rapidly formed at pH 4.55 only slowly to convert into competitive S-bound complexes with κ2N1,S and K2N′met,S co-ordination. After reaching a quasi-stationary state (50 h), amide N′met anchoring in the latter species facilitates co-ordination of the adjacent amino nitrogen to afford the thermodynamically preferred κ2N (amino),N′met chelate. At a 2:1 molar ratio, slow reaction of the macrochelate with a second (en)PtII fragment led to formation of [{Pt(en)}2(hisH-1-Hmet-1κ2N,N 3:2κ2N1,S)]3+. In met-Hhis, κ2N (amino),S chelation is kinetically and thermodynamically preferred in acid solution. At pH 9.6, however, sulfur binding is thermodynamically unfavourable, and the initially formed κ2N (amino),S complex slowly converts into a κ2N (amino),N′his species, which subsequently affords [Pt(en-κN){met-his-κ3N (amino),N′his,N3}]+ on cleavage of the Pt-N (en) bond trans to the amino N atom.

Interaction of (amine)M(II) complexes (amine=dien, en; M=Pd, Pt) with purine nucleoside 2′-, 3′- and 5′-monophosphates - The role of the phosphate site for specific metal fragment-nucleotide recognition by macrochelation

The pH-dependent interaction of [Pd(dien)(H2O)]2+ with adenosine and guanosine 2′- and 3′-monophosphates at molar ratios R=1 and 3 has been studied by potentiometric and NMR techniques. The absence of additional intramolecular stabilisation of the N7 coordination mode by (amine)N-H?O(phosphate) hydrogen bonding, as for 5′-AMP2- or 5′-GMP3-, leads to reversal of the intrinsic binding ratio log[β(BM1)/β(M7B)] in favour of N1 coordination for mononuclear (dien)Pd(II) complexes of the purine 2′- and 3′-nucleotides. Outer-sphere κ2N7,O(phosphate) macrochelation is also responsible for the formation of a specific μ-N1,N7 bridged cyclic tetramer [{(en)Pd(5′-GMP)}4]4- in the pH range 5.5-9.5. Both inner- and outer-sphere κ2N3,O(phosphate) macrochelation lead at R=3 to a dramatic enhancement of (en)Pd(II) binding to N3 of 2′-GMP3- in comparison to 3′- or 5′-GMP3-. Reaction of [{Pt(dien)}2(2′-GMP-μ-N1,N7)]+ with [Pt(en)(H2O)2]2+ affords both types of macrochelate at approximately 1:1 ratio, namely [{Pt(dien)}2(2′-GMP-μ3-N1,N3,N7,O(P)){Pt(en)} 3+ and [{Pt(dien)}2(2′-GMP-μ3-N1,N3,N7) {Pt(en)H2O)}]3+ with respectively direct (en)Pt-O(phosphate) and outer-sphere (amine)N-H?O(phosphate) hydrogen bonding. Following HPLC separation, these trinuclear products could be characterised by NMR and FAB-MS.

Synthesis and kinetic studies of nonelectrolytic binuclear platinum and palladium bromide complexes

Nonelectrolytic binuclear platinum and palladium complexes with bridging and terminal bromide ligands were synthesized by reacting K 2[PdBr4] with [M(AH2O)2](NO 3)2 (M = Pt, Pd; A = NH3, 1/2en) and K 2[PtBr4] with [Pd(en)(H2O)2](NO 3)2. The kinetics of the interaction of the obtained compounds with KI was studied. Copyright

Dimethyl sulfoxide as a ligand in binuclear platinum(II) complexes

Binuclear platinum(II) complexes in which dimethyl sulfoxide molecules function as terminal and bridging ligands were prepared by a reaction between platinum(II) diamine compounds.

Cationic binuclear platinum(II) complexes with bromide bridges

Binuclear platinum(II) complexes with bromide bridges were prepared by a reaction between platinum(II) diammine compounds.

Nonelectrolytic bromide-bridged binuclear platinum(II) complexes

Nonelectrolytic binuclear platinum(II) complexes and mixed-valence compounds in which bromine atoms coordinated to two platinum atoms were prepared by the interaction of cis-diaqua-diammineplatinum(II) with K 2[PtBr4] and K2[PtBr6].

pH-Dependent competition between N2S and N,N' chelation in the reaction of 2+ (en=H2NCH2CH2NH2) with methionine-containing di- and tri-peptides

Products of the reaction of the cisplatin analogue 2+ (en=ethane-1,2-diamine) with methionine (Hmet)-containing di- and tri-peptides in the range pH 2.5-11.0 have been separated by semi-preparative reversed-phase HPLC with perfluorinated carboxylic acids as ion-pairing agents.Structural characterisation of the (en)PtII complexes of met-Hxaa (met-Hgly, met-gly-Hgly) and xaa-Hmet (gly-Hmet, gly-met-Hgly, gly-gly-Hmet) peptides with respectively N-terminal methionine or glycine (Hgly) units was achieved by multinuclear NMR spectroscopy.The κ2N (amino),S (thiother) and κ2N (amino),N' (amide) chelation modes are competitive for met-Hxaa peptides with the former mode predominating at pH2N' (amide),S (thioether)-co-ordinated species are observed for xaa-Hmet peptides in acid solution with cleavage of a Pt-N (en) bond leading to competitive κ3N (amino),N' (amide),S (thioether) complexes for gly-Hmet and gly-met-Hgly.At pH>7.4, the κ2N,N' complexes dominate for these bioligands as for met-Hxaa peptides.This is not the case for gly-gly-Hmet, for which only one major species with κ2N'' (amide),S (thioether) co-ordination is found at pH10.6.

Dinuclear (Pt,Pt) and heteronuclear (Pt,Pd) complexes of uracil nucleobases with identical and mixed amine (NH3, en, bpy) ligands on the two metals. Effects of the heterometal and amine on the oxidizability

The preparation is reported of a series of dinuclear complexes of composition [(X2)PtL2M(Y2)]Z·nH2O with L = 1-methyluracil anion (1-MeU, C5H5N2O2) or 1-methylthymine anion (1-MeT, C6H7N2O2) bound to Pt via the N3 position and the second metal M (PtII, PdII) coordinated through the two O4 positions of the L ligands. X2 and Y2 are any of the following amines: ammonia, (NH3)2; ethylenediamine, en; 2,2′-bipyridine, bpy. The complexes were characterized by elemental analysis, by spectroscopic methods (IR, Raman, 1H NMR, UV), and, in the case of cis-[(NH3)2Pt(1-MeU)2Pd(en)](NO 3)2·6H2O (4a), by X-ray analysis. 4a crystallizes in the triclinic space group P1, with a = 11.698 (2) A?, b = 11.796 (2) A?, c = 12.965 (2) A?, α = 114.94 (1)°, β = 100.29 (1)°, γ= 111.69 (1)°, V = 1383.5 A?3, and Z = 2. The two 1-MeU ligands adopt a head-head orientation, with cis-Pt(NH3)2 coordination through N3 and (en)Pd coordination through O4. The Pt-Pd separation within the cation is 2.927 (1) A?. Dinuclear cations are stacked in such a way that Pt atoms of adjacent dinuclear units face each other (Pt?Pt = 4.553 (1) A?) and likewise Pd atoms are next to each other (Pd?Pd = 3.255 (1) A?). Oxidation of Pt,Pt and Pt,Pd complexes by means of CeIV in 0.7 M H2SO4 has been studied. [PtII]2 complexes are oxidized without exception to the corresponding [PtIII]2 compounds, whereas [PtIIPdII] complexes give a mixture of mononuclear [PtIV] and [PdII] complexes. With [PtII]2 complexes, tetranuclear, mixed-valence Pt(2.25) species were observed as intermediates whenever the Y2 entity was planar ((NH3)2, bpy), specifically for the following combinations: X2 = Y2 = (NH3)2, X2 = Y2 = bpy, X2 = (NH3)2 and Y2 = bpy, X2 = en and Y2 = (NH3)2. In contrast, for Y2 = en, no Pt(2.25) species were detected by using visible spectroscopy. Standard redox potentials for the respective oxidation steps were determined by use of a standardized Pt electrode. Introduction of en ligands into the dinuclear [PtII]2 complexes at either side (X2 and/or Y2) raised the redox potential for the [PtII]2/[PtIII]2 couple relative to that of the (NH3)2 analogue slightly, while introduction of bpy ligands led to a significant increase in E°.

Reaction of α-pyridone with diaquo(ethylenediamine)platinum(II). Synthesis and structure of the head-to-head isomer of bis(μ-2-pyndonato-N,O)bis[(ethylenediamine)platinum(II)] nitrate

The head-to-head isomer of the dimeric compound [Pt2(en)2(C5H4NO) 2](NO3)2 has been synthesized in the reaction of [Pt(en)(H2O)2]2+ with α-pyridone (C5H4NHO). An X-ray structural study of this compound shows that, like its cis-diammineplatinum(II) analogue, it forms a dimer of dimers in the solid state. The Pt-Pt distances of 2.992 (1) A? for the α-pyridonate-bridged binuclear unit and 3.236 (1) A? for the interdimer separation are each ～0.1 A? longer than the corresponding values in the cis-diammineplatinum(II) complex. This increase in the Pt-Pt distances is attributed to steric repulsion between adjacent in-plane ligands, which is greater in the ethylenediamine complex. The steric interaction also affects the chemical reactivity of the [Pt2(en)2(C5H4NO)2] 2+ cation, which preliminary work shows to isomerize more readily and to be more stable toward oxidation to the Pt(III) dimer with nitric acid than the diammine analogue. The compound crystallizes in the monoclinic system, space group P21/c, with a = 12.169 (2) A?, b = 10.860 (1) A?, c = 17.282 (3) A?, β = 103.11 (2)°, V = 2224 A?3, and Z = 4. Refinement converged at R1 = 0.033.