The synthesis, spectroscopy, structures and chemical reactivity of platinum(II) diolefin complexes cis‐[(∥∧∥)PtCl2], cis‐[(∥∧∥)PtCl(R)] and cis‐[(∥∧∥)Pt(R)2] [∥∧∥ = chelate diolefin ligand: 1,5‐cyclooctadiene (COD), 1,5‐dimethylocta‐1,5‐diene (Me2COD), norbornadiene (NBD), 1,5‐hexadiene (HEX), 3‐allyloxypropene (All2O, diallyl ether), diallylamine (All2NH); R = Me, Bn, C6F5, C6F4H‐4 (or ‐5), or C≡C(4‐Me)Ph] have been explored. The relative exchange rates of the cis‐[(∥∧∥)PtCl2] complexes towards the diimine ligand diisopropyl‐1,4‐diazabutadiene (iPr‐DAB) increased along the series COD < Me2COD < NBD < HEX < All2O by a factor of 4. The presumably dimeric complex [(All2NH)PtCl2]2 undergoes a unique rearrangement process in dimethyl sulfoxide (DMSO) solution to yield the dimeric piperazine complex [PtCl(dmso)(C6H10N)]2, which has been characterised by single‐crystal XRD. For selected platinum complexes, cytotoxic effects in HT‐29 colon carcinoma and MCF‐7 breast cancer cell lines were evaluated. For comparison, the dicationic complexes [(COD)Pt(Bn)(L)][PF6]2 with the very labile coligands N‐methyl‐4,4′‐bipyridinium (MQ+) and N‐methyl‐1,4‐pyrazinium (Mpz+) were added to the study. Although the hexadiene complexes [(HEX)Pt(C6F4H‐4)2] and [(HEX)Pt(C6F4H‐5)2] show strong cytotoxicity, the introduction of labile diolefin ligands or the labile cationic MQ+ or Mpz+ coligands does not generally lead to markedly increased cytotoxicity.

New organometallic complexes [M(dppe)(R)] {where M = Pt or Pd, dppe = 1,2-bis(diphenylphosphano)ethane, and R = CFH-x (x = 6,5,4), CFH-3,5, CFH-5,6, CFH-3,6, CF(OMe)-4, and CF(cyclo-CHN)-4, the numbers x refer to the positions of the protons in the polyfluoroaryl ligands} were synthesised either through transmetalation from the dichlorido complexes [M(dppe)Cl] or through ligand exchange using [M(diene)Cl] precursor complexes with diene = 1,5-cyclooctadiene (cod) or 1,5-hexadiene (hex). Alternatively, [M(dppX)Cl(R)] complexes with dppX = dppm (1,1-bis(diphenylphosphano)methane), dppe, dppp (1,3-bis(diphenylphosphano)propane), and dppb (1,4-bis(diphenylphosphano)butane) were prepared in decarboxylation reactions from thallium(i) carboxylates Tl(OCR). The different preparative methods were compared in terms of yield and purity. Structural and spectroscopic data are reported for the new dppX- and diene-M(R) complexes. Antiproliferative activity was investigated for these new complexes against the HT-29 (colon carcinoma) and MCF-7 (breast adenocarcinoma) cell lines, and the active compounds of this first series together with organometallic dppX or hex Pt or Pd complexes were then included in cell tests using L1210 (leukaemia cells) and the cisplatin-resistant L1210/DDP cell line. Remarkably, promising antiproliferative results were found for a few Pt and Pd complexes, while structurally closely related compounds were essentially nontoxic.

A series of fluorinated bis(aryl)platinum(II) complexes, cis-[Pt(Ar(f))2(1,5-C6H10)] (Ar(f) = p-C6HF4, p-C6(OMe)F4 or C6H2F(3-)2,4,6) were reacted with the four-membered gallium(I) or indium(I) heterocycles, [:E{[N(Ar)]2CN(C6H11)2}] (E = Ga or In, Ar = C6H3Pr(i)(2-)2,6) under various stoichiometries. These yielded either the 2:1 complexes, cis-[Pt(Ar(f))2{Ga{[N(Ar)]2CN(C6H11)2}}2], trans-[Pt(C6H2F(3-)2,4,6)2{Ga{[N(Ar)]2CN(C6H11)2}}2] and trans-[Pt(Ar(f))2{In{[N(Ar)]2CN(C6H11)2}}2], or the 3:1 complexes, trans-[Pt(Ar(f))2{In{[N(Ar)]2CN(C6H11)2}}3] (Ar(f) = p-C6HF4 or p-C6(OMe)F4), all of which were crystallographically characterised. The differing outcomes of these reactions are explained in terms of the lesser nucleophilicity and greater electrophilicity of the indium heterocycle relative to its gallium counterpart. In the solid state, and in solution, the 3:1 indium complexes exhibit strong intramolecular In...F interactions which are indicative of their heterocyclic ligands displaying rare examples of "Lewis amphoteric" behaviour. An unusual platinum(0) complex in which the indium(I) heterocycle acts as a mu3-bridging ligand, [{Pt(norbornene)}3{mu3-In{[N(Ar)]2CN(C6H11)2}}2], was also prepared and structurally authenticated.

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Reactions of PtCl 2 (cod) (cod = cycloocta-1,5-diene) with 2,4,6-trifluoro-and 2,3,4,5-tetrafluoro-phenyllithium in diethyl ether gives Pt(C 6 H 2 F 3 -2,4,6) 2 (cod) (1) (monoclinic, P2 1 /n, Z = 4, a = 7.141(1), b = 15.002(2), c = 17.071(3) A Ê , b = 91.37(2)°) and Pt(C 6 HF 4 -2,3,4,5) 2 (cod) (2) (triclinic, P 1, Z = 2, a = 10.150 (2), b = 10.762(2), c = 10.812(2) A Ê , a = 63.606(3), b = 63.327(3), c = 76.496(3)°)respectively, which have two ipso carbon atoms and two double bond midpoint centres in a square planar arrangement, and aromatic rings angled near perpendicular to the coordination plane.Zwei Platindien-Synthesereagentien Pt(C 6 H 2 F 3 -2,4,6) 2 (cod) und Pt(C 6 HF 4 -2,3,4,5) 2 (cod) Inhaltsu È bersicht. Die Umsetzungen von PtCl 2 (cod) (cod = cycloocta-1,5-dien) mit 2,4,6-Trifluoro-bzw. 2,3,4,5-Tetrafluoro-phenyllithium in Diethylether fu È hrt zu Pt(C 6 H 2 F 3 -2,4,6) 2 (cod) (1) (monoklin, P2 1 /n, Z = 4, a = 7,141(1), b = 15,002(2), c = 17,071(3) A Ê , b = 91,37(2)°) und Pt(C 6 HF 4 -2,3,4,5) 2 (cod) (2) (triklin, P 1, Z = 2, a = 10,150 (2), b = 10,762(2), c = 10,812(2) A Ê , a = 63,606(3), b = 63,327(3), c = 76,496(3)°). In beiden Strukturen liegt eine quadratischplanare Koordination mit zwei ipso-Kohlenstoffatomen und zwei Mittelpunkten von Doppelbindungen vor. Die aromatischen Ringe stehen nahezu senkrecht auf der Koordinationsebene.

From the reaction of PtCl 2 (hex) (hex = hexa-1,5diene) with LiC 6 F 5 in diethyl ether, the complex [Pt{CH(CH 2 C 6 F 5 )CH 2 CH 2 CH=CH 2 }(C 6 F 5 )(OH 2 )] (1) was isolated. The crystal structure (monoclinic, C2/c (no. 15), Z = 8, a = 15.241(3), b = 16.579(2), c = 16.225(2) A Ê , b = 111.12(2)°) shows a complex with square planar coordination around platinum with a template formed 1-pentafluorophenylhex-5-en-2-yl ligand, and C 6 F 5 and aqua ligands trans to the double bond and alkyl carbon, respectively.