Search

A reaction in anhydrous toluene between the formally unsaturated fragment [Ln(hfac)3] (Ln3+ = Eu3+, Gd3+ and Er3+; Hhfac = hexafluoroacetylacetone) and [Al(qNO)3] (HqNO = 8-hydroxyquinoline N-oxide), here prepared for the first time from [Al(OtBu)3] and HqNO, affords the dinuclear heterometallic compounds [Ln(hfac)3Al(qNO)3] (Ln3+ = Eu3+, Gd3+ and Er3+) in high yields. The molecular structures of these new compounds revealed a dinuclear species with three phenolic oxygen atoms bridging the two metal atoms. While the europium and gadolinium complexes show the coordination number (CN) 9 for the lanthanide centre, in the complex featuring the smaller erbium ion, only two oxygens bridge the two metal atoms for a resulting CN of 8. The reaction of [Eu(hfac)3] with [Alq3] (Hq = 8-hydroxyquinoline) in the same conditions yields a heterometallic product of composition [Eu(hfac)3Alq3]. A recrystallization attempt from hot heptane in air produced single crystals of two different morphologies and compositions: [Eu2(hfac)6Al2q4(OH)2] and [Eu2(hfac)6(µ-Hq)2]. The latter compound can be directly prepared from [Eu(hfac)3] and Hq at room temperature. Quantum mechanical calculations confirm (i) the higher stability of [Eu(hfac)3Al(qNO)3] vs. the corresponding [Eu(hfac)3Alq3] and (ii) the preference of the Er complexes for the CN 8, justifying the different behaviour in terms of the Lewis acidity of the metal centre. [ABSTRACT FROM AUTHOR]

While ruthenium(II) arene complexes have been widely investigated for their potential in catalytic transfer hydrogenation, studies on homologous compounds replacing the arene ligand with the six‐electron donor tris(1‐pyrazolyl)methane (tpm) are almost absent in the literature. The reactions of [RuCl(κ3‐tpm)(PPh3)2]Cl, 1, with a series of nitrogen ligands (L) proceeded with selective PPh3 mono‐substitution, affording the novel complexes [RuCl(κ3‐tpm)(PPh3)(L)]Cl (L=NCMe, 2; NCPh, 3; imidazole, 4) in almost quantitative yields. Products 2–4 were fully characterized by IR and multinuclear NMR spectroscopy, moreover the molecular structure of 4 was ascertained by single crystal X‐ray diffraction. Compounds 2–4 were evaluated as catalytic precursors in the transfer hydrogenation of a series of ketones with isopropanol as the hydrogen source, and 2 exhibited the highest activity. Extensive NMR experiments and DFT calculations allowed to elucidate the mechanism of the transfer hydrogenation process, suggesting the crucial role played by the tpm ligand, reversibly switching from tri‐ to bidentate coordination during the catalytic cycle. [ABSTRACT FROM AUTHOR]

Diiron μ-aminocarbyne complexes [Fe2Cp2(NCMe)(CO)(μ-CO){μ-CN(Me)(R)}]CF3SO3 (R = Xyl, [1aNCMe]CF3SO3; R = Me, [1bNCMe]CF3SO3; R = Cy, [1cNCMe]CF3SO3; R = CH2Ph, [1dNCMe]CF3SO3), freshly prepared from tricarbonyl precursors [1a–d]CF3SO3, reacted with NaOCN (in acetone) and NBu4SCN (in dichloromethane) to give [Fe2Cp2(kN-NCO)(CO)(μ-CO){μ-CN(Me)(R)}] (R = Xyl, 2a; Me, 2b; Cy, 2c) and [Fe2Cp2(kN-NCS)(CO)(μ-CO){μ-CN(Me)(CH2Ph)}], 3 in 67–81% yields via substitution of the acetonitrile ligand. The reaction of [1aNCMe–1cNCMe]CF3SO3 with KSeCN in THF at reflux temperature led to the cyanide complexes [Fe2Cp2(CN)(CO)(μ-CO){μ-CNMe(R)}], 6a–c (45–67%). When the reaction of [1aNCMe]CF3SO3 with KSeCN was performed in acetone at room temperature, subsequent careful chromatography allowed the separation of moderate amounts of [Fe2Cp2(kSe-SeCN)(CO)(μ-CO){μ-CN(Me)(Xyl)}], 4a, and [Fe2Cp2(kN-NCSe)(CO)(μ-CO){μ-CN(Me)(Xyl)}], 5a. All products were fully characterized by elemental analysis, IR, and multinuclear NMR spectroscopy; moreover, the molecular structure of trans-6b was ascertained by single crystal X-ray diffraction. DFT calculations were carried out to shed light on the coordination mode and stability of the {NCSe-} fragment. [ABSTRACT FROM AUTHOR]

Mononuclear RuII complex [RuCl(κ3N‐tpm)(κ2N‐bptz)]Cl, [1]Cl [tpm=tris(1‐ pyrazolyl)methane; bptz=3,6‐di(2‐pyridyl)‐1,2,4,5‐tetrazine], and dinuclear complexes [RuCl(κ3N‐tpm)(μ‐κ2N:κ2N‐bptz)Ru(κ2N‐bipy)2][PF6]3, [3][PF6]3, [RuCl(η6‐p‐cymene)(μ‐κ2N:κ2N‐dpp)Ru(κ2N‐bipy)2][PF6]2, [4][PF6]2, and [RuCl(η6‐p‐cymene)(μ‐κ2N:κ2N‐dpp)Ru(κ2N‐biqn)2][PF6]3, [5][PF6]3 [dpp=2,3‐bis(2′‐pyridyl)‐pyrazine; bipy=2,2′‐bipyridine; biqn=2,2′‐quinoline], incorporating both potentially catalytic and photosensitive subunits, were synthesized and characterized by means of elemental analysis, mass spectrometry, and spectroscopic methods. The molecular structures of the new compounds were also investigated and compared by means of DFT calculations. The absorption spectra of all the compounds are dominated by metal‐to‐ligand charge‐transfer bands in the visible (which in most cases largely extend over the red portion of the spectrum) and ligand‐centered bands in the UV region. The oxidation behavior is based on metal‐centered RuII to RuIII oxidation processes, which in phosphate buffer solution are followed by a catalytic water oxidation wave for [1]Cl and [3][PF6]3. For these compounds, the mechanism of water oxidation is proposed to consist in water nucleophilic attack, according to chemical experiments with Ce(IV) salts, so demonstrating for the first time that the bptz ligand can be profitably used to build ruthenium(II) complexes with catalytic properties. On the contrary, no catalytic process is observed for 4 and 5, most likely due to the high positive potential for RuII oxidation induced by the presence of the p‐cymene moiety. [ABSTRACT FROM AUTHOR]

The diiron µ‐vinyliminium compounds [Fe2Cp2(CO)(µ‐CO){µ‐η1:η3‐C3HC2HC1NMe(R)}]CF3SO3 (R = Me, 2a; R = Xyl = 2,6‐C6H3Me2, 2b; Cp = η5‐C5H5) reacted with grey selenium, in the presence of sodium methoxide, to give the corresponding Se‐functionalized derivatives [Fe2Cp2(CO)(µ‐CO){µ‐η1:η3‐C3HC2(Se)C1NMe(R)}], 3a–b, in ca. 50 % yields. The monoiron zwitterionic complex [FeCp(CO){SeC1(NMe2)C2HC3H}], 4, was obtained as a side‐product (31 %) of the reaction leading to 3a. The treatment of 3b with S8/NaOMe afforded the 2‐ferra‐thiophene [FeCp(CO){SC3HC2HC1NMe(Xyl)}], 5, in 49 % yield. The straightforward reactions of 3a with a two‐fold excess of dialkylacetylenedicarboxylates led to functionalized 3‐amino‐selenophenes appended to the diiron frame through a bridging allylidene ligand, [Fe2Cp2(CO)(µ‐CO){µ‐η1:η3‐C7(CO2R)C6(CO2R)C3HC2SeC5(CO2R)C4(CO2R)C1(NMe2)}] (R = Me, 6a; R = Et, 6b; R = tBu, 6c), in approximately 50 % yields. The synthesis of 6a–c is the result of two distinct modes of reactivity exhibited by the alkyne reactant in one pot, i.e. 1,3‐dipolar cycloaddition to C and Se atoms and insertion into Fe‐µ‐alkylidene. All the products were characterized by means of elemental analysis, IR and multinuclear NMR spectroscopy, and the molecular structure of 6a was elucidated by a single‐crystal X‐ray diffraction study. [ABSTRACT FROM AUTHOR]

The reactions of [WCl6] with a series of ethers have been performed in chlorinated solvent and elucidated by means of analytical, spectroscopic and DFT methods. The addition of tetrahydropyran (thp) or 1,4-dioxane to [WCl6] resulted in the reversible formation of the adducts WCl6... [L = thp (1a), 1,4-dioxane (1b)], detected in solution by NMR spectroscopy. The reaction of [WCl6] with thp in a molar ratio of 1:2 in chloroform at reflux afforded [WOCl4(thp)] (2a), which was isolated in 51% yield. [WOCl4(OMe2)] (2b) and [WOCl3(OMe2)2](3a) were isolated in yields of 53 and 18 %, respectively, from the reaction of [WCl6] with an excess of dimethyl ether. [WOCl3(OEt2)2](3b) was the only identified metal compound produced from the reaction of [WCl6] and OEt2 (1:2 molar ratio). According to NMR studies, the oxide ligand in 2a,b and 3a,b was generated by double C-O bond cleavage involving one equivalent of organic reactant. The 1:1 reaction of [WCl6] with 1,2-diethoxyethane led to [WCl5(κ²-OCH2CH2OEt)] (4) and a minor amount of [WCl4(κ² EtOCH2CH2OEt)] (5). The aryl oxide compound [WCl5(OPh)] (6) was prepared in 62 % yield from the reaction of [WCl6] and anisole by selective Csp3--O bond activation. The prolonged heating of a mixture of [WCl6] and diphenyl ether in 1,2-dichloroethane led to the isolation of the WV complex [WCl5(OPh2)] (7). The molecular structures of 2a and 3a were ascertained by X-ray diffraction. [ABSTRACT FROM AUTHOR]

The 1 : 1 molar reactions of niobium and tantalum pentahalides with the monodentate NHC ligand 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (Ipr), in toluene (or benzene) at ca. 80 °C, afforded the complexes NbX5(Ipr) (X = F, 2; Br, 3) and TaX5(Ipr) (X = F, 4; Cl, 5; Br, 6), in generally good yields. Complexes 2–6 represent uncommon cases of stable NHC adducts of metal halides with the metal in an oxidation state higher than +4, and also rare examples of Nb–NHC and Ta–NHC bonding systems. In particular, the X-ray molecular structure determined for 6 provides the unprecedented crystallographic characterization of a tantalum compound with a monodentate NHC ligand. DFT results indicate that the metal–carbon bond in 2–6 is a purely σ one. According to NMR studies (1H, 13C, 93Nb), the formation of 3, 5, 6, as well as the previously communicated NbCl5(Ipr), 1, proceeded with the intermediacy of [MX6]− salts, presumably due to steric reasons. On the other hand, the intermediate formation of MF6− in the pathways to 2 and 4 was not observed, according to 19F (and 93Nb in the case of 2) NMR. DFT calculations were carried out in order to shed light on structural and mechanistic aspects, and allowed to trace possible reaction routes. [ABSTRACT FROM AUTHOR]

Several mono- or bis-alkynyl derivatives of general formula Pt6(μ-PBut2)4(CO)4X(C≡C–R), Pt6(μ-PBut2)4(CO)4(C≡C–R)2 or Pt6(μ-PBut2)4(CO)4(C≡C–R)(C≡C–R′) were obtained under Sonogashira type conditions. The new clusters have been characterized with microanalysis and using IR and multinuclear NMR spectroscopy. The crystal and molecular structures of Pt6(μ-PBut2)4(CO)4(C≡C–R)2 (R = H, C6H4-4-n-C5H11) are presented and electrochemical and spectroelectrochemical studies of some representative compounds are also reported. [ABSTRACT FROM AUTHOR]

The zwitterionic bridging vinyliminium complex [Fe2{μ-η1:η3-C(Tol)ᆖC(CS2)CᆖN(Me)2}(μ-CO)(CO)(Cp)2] (5a) undergoes the addition of two equivalents of MeO2C–C≡C–CO2Me affording the bridging bis-alkylidene complex [Fe2{μ-η1:η3-C(Me)C{C(CO2Me)C(CO2Me)CSC(CO2Me)C(CO2Me)S}CNMe2}(μ-CO)(CO)(Cp)2] (6). One alkyne unit inserts into a C–CS2 bond of the bridging ligand, with consequent rearrangement that leads to the formation of a diene. The reaction shows analogies with the enyne metathesis. The second alkyne is incorporated into the bridging frame via cycloaddition at the thiocarboxylate function, affording a 1,3-dithiolene. The complexes [Fe2{μ-η1:η3-C(R′)ᆖC(CS2)CᆖN(Me)(R)}(μ-CO)(CO)(Cp)2] (R = Xyl, R′ = Tol, 5b; R = p-C6H4OMe, R′ = Me, 5c; Xyl = 2,6-Me2C6H3), treated with MeO2C–C≡C–CO2Me and then with HBF4, undergo the cycloaddition of the alkyne with the dithiocarboxylate group and protonation of the dithiocarboxylate carbon, affording the complexes [Fe2{μ-η1:η3-C(R′)ᆖC{C(H)SC(CO2Me)C(CO2Me)S}CᆖN(Me)(R)}(μ-CO)(CO)(Cp)2][BF4] (R = Xyl, R′ = Tol, 7a; R = p-C6H4OMe, R′ = Me, 7b), respectively. [ABSTRACT FROM AUTHOR]

Abstract: Co(II), Ni(II), Cu(II) and Cd(II) coordination polymers containing the flexible ditopic bis(1,2,4-triazol-1-yl)methane ligand (Btm) have been prepared by reaction of equimolar quantities of the corresponding cobalt, nickel, copper and cadmium salts in EtOH solution. Structure solution and refinement of polycrystalline materials were performed by powder diffraction technique (XRPD), using conventional laboratory data. The results show that architecturally different coordination polymers were obtained depending on the counter-ion employed. The XRPD results show also that non-covalent interactions are driving forces for the occurrence of different structures. [Copyright &y& Elsevier]

Crystals of trans-Pt2(μ-X)2X2(CO)2 (X = Br, I) have been grown and their molecular and crystalline structures have been solved by X-ray diffraction methods. In both cases the dinuclear molecules are bent, with a bending angle of 164.6° and 156.5° for the bromide and the iodide, respectively. While the structure of the bromo-derivative is reported here for the first time, a modification of trans-Pt2(μ-I)2I2(CO)2 with planar centrosymmetric molecules is known. This appears to be a rare case of a platinum(II) halo-bridged derivative structurally characterized in both bent and planar forms. [ABSTRACT FROM AUTHOR]

Abstract: The diiron complex [Fe2{μ-к1(O):η1(C):η3(C)–C(N(Me)(Xyl))C(H)OMe}(μ-CO)(Cp)2] (2) has been obtained from the diiron bridging vinyliminium [Fe2{μ-η1:η3–C(Me)glyph name="dbnd" />N(Me)(Xyl)}(μ-CO)(CO)(Cp)2][SO3CF3] (1; Xyl = 2,5-C6H3Me2) upon treatment with NaH in the presence of CH2 h name="dbnd" />CMe2, followed by chromatography on alumina with MeOH as eluent. The reaction consists in the incorporation of a methylcarboxylate unit, assembled from CO and MeO−, into the bridging vinyliminium ligand. The resulting complex 2 exhibits a C4 fragment bridging the two iron centres through the carbonyl oxygen atom and the allylidene moiety. The X-ray molecular structure of 2 has been determined. [Copyright &y& Elsevier]

Abstract: The computed structures of the long-lived radical cation salts [Arene][Nb2F11] [Arene = 1,4-F2-2,5-(OMe)2C6H2, 2; 1,4-(OMe)2C6H4, 3; 2,5-(OEt)2(Me)C6H3, 4; C6H6, 5] and that of the transient [1,3-(OMe)2C6H4][Nb2F11], 6, obtained for the gas-phase by DFT at the B3LYP/6-31G∗∗ level, are presented. The degree of inertness observed in chloroform solution seems to increase on decreasing the steric demand of the ring substituents, and may be correlated to the calculated distance between the cation-centroid and the niobium atoms. The room-temperature EPR spectra of 2–4, in CHCl3, are described in detail; the spectrum of 3 is compared to those of analogous 1,4-dimethoxybenzene radical species reported previously. The EPR spectra display a hyperfine structure due to coupling of the unpaired electron with nuclei belonging to both the cation (H and F in the case of 2) and the anion (F and eventually Nb). The UV–Vis spectra of 2–4 exhibit one strong absorption attributed to the cation and one anion-to-cation charge-transfer band (e.g. for 3 at 398 and 589 nm, respectively). Thermodynamic calculations indicate that the low yield formation of the benzene radical salt 5 occurs with Gibbs free energy variation significantly higher than those involved in the synthesis of 2–4 and 6. [Copyright &y& Elsevier]

Abstract: Novel triorganotin(IV) derivatives of β-diketonate Q ligands (HQ in general, in detail HQfur =1-phenyl-3-methyl-4-(2-furancarbonyl)-pyrazol-5-one, HQthi =1-phenyl-3-methyl-4-(2-thienylcarbonyl)-pyrazol-5-one) of general formula (Q)SnR3·xH2O (R=Ph, x =0; R=Bu n or Me, x =1) have been synthesized and spectroscopically and thermally characterized. Triphenyltin(IV) complexes have been isolated as anhydrous compounds while trialkyltin(IV) are always monohydrated. The structures of (Qfur)SnPh3 and (Qthi)SnMe3(OH2) are recorded. The tin atoms are five-coordinate in both. In the first, the pyrazolonate ligand behaves as an O,O′-bidentate; there are two similar but independent molecules in the structure. In the quasi-trigonal-bipyramidal environments, Sn–O(acyl) are 2.478(3), 2.364(3), Sn–O(pyrazolonate) 2.050(2), 2.079(2), Sn–C 2.123(4)–2.162(3)Å with the longer O(acyl) and a phenyl group quasi-trans (O–Sn–C 162.5(1), 160.8(1)°). In (Qthi)SnMe3(OH2), the three methyl groups are equatorial (Sn–C 2.1259(9)–2.1380(8)Å); Sn–O(Qthi,OH2) are 2.2143(5), 2.3350(6)Å, O–Sn–O 175.36(2)°. Trimethyltin(IV) derivatives decompose on heating with release of H2O and SnMe4 and formation of (Q)2SnMe2. Decomposition occurs also within two days after dissolution of (Q)SnMe3(OH2) in chloroform. [Copyright &y& Elsevier]

Abstract: Syntheses, spectroscopic and thermal characterization are reported for the potentially tetradentate bis(O,O′-4-acyl-5-pyrazolone) pro-ligands HQ3QH and HQ4QH (in detail HQ3QH: 1,5-bis(5-hydroxy-1-phenyl-3-methyl-1H-pyrazol-4-yl)pentane-1,5-dione, HQ4QH: 1,6-bis(5-hydroxy-1-phenyl-3-methyl-1H-pyrazol-4-yl)hexane-1,6-dione) and their di-n-butyltin(IV) derivatives and . Single crystal X-ray structural characterizations of the proligand HQ4QH and of the binuclear tin(IV) complex are also reported; both the ligand and complex molecules are centrosymmetric, the latter having two independent molecules in the structure. Sn–C, O(acyl), O(pz) distances (〈〉) are 2.121(3), 2.119(6) and 2.37(4)Å. [ABSTRACT FROM AUTHOR]

Abstract: Nine new organotin complexes, namely [SnR2XY(BtzH)2] (1: R=Me, X=Y=Cl, 2: R=Me, X=Y=Br, 3: R= n Bu, X=Cl, Y=OH; 4: R=Ph, X=Y=Cl; 5a: R=Me, X=Y=NO3; 5b: R=Me, X=Y=ClO4) and [SnR2X2(5-NO2indH)2] (6: R=Me, X=Cl; 7: R= n Bu, X=Cl; 8: R=Me, X=5-NO2ind) were obtained by reaction of SnR2X2 with BtzH (1,2,3-benzotriazole) and 5-NO2indH (5-nitroindazole). These compounds were characterized by IR, NMR and ESI MS, and 1 is shown by a single crystal X-ray study to comprise mononuclear centrosymmetric molecules, all pairs of ligands being mutually opposed in a quasi-octahedral coordination sphere. Sn–Cl, C, N are 2.5700(5), 2.108(2), 2.357(2)Å. A new triclinic () polymorph of the binuclear [{ t Bu2ClSn(μ-OH)}2], 9 is also described (cf. the earlier monoclinic (P21/c)). The unit cell contents comprise a pair of centrosymmetric dimers: Sn–O are 2.042(4)–2.215(4), Sn–Cl 2.489(2), 2.491(2), Sn–C 2.166(6)–2.203(7) Å, O–Sn–O 68.4(2) (x2), and Sn–O–Sn 111.6(2)° (x2). [ABSTRACT FROM AUTHOR]

Abstract: Lanthanide coordination compounds are important due to their unique luminescence and magnetic properties. Direct synthesis of oligo- and polymeric Ln complexes with a predicted structure is hampered due to high coordination numbers and unstable coordination polyhedra. A «building blocks» strategy for the synthesis of Ln(Q)3L polymers (Ln=Eu, Tb or Gd; HQ=1-phenyl-3-methyl-4-RC(-5-one in general, in detail HQS, R=thienyl; HQCP: R=cyclopentyl; L=bis(diphenylphosphine)methane dioxide dppMO2, bis(diphenylphosphine)ethane dioxide dppEO2, and bis(diphenylphosphine)butane dioxide dppBO2) has been used: {Ln(Q)3} mononuclear fragments have been linked by dppXO2 bridges when X=E or B, while monomeric molecular derivatives have been isolated with dppMO2. Eighteen new complexes were prepared, 12 of them showing a polymeric nature and 6 being monomers. Three compounds have been structurally characterized, further confirming the hypothesized connectivity where metal centers have been found to exist in LnO8 square antiprismatic environments. Luminescence properties have been also investigated. [ABSTRACT FROM AUTHOR]

Abstract: A series of Cu(II), Zn(II) and Mn(II) coordination compounds has been synthesized by reaction of the corresponding metal salts and pyrazolyl-based ligands, i.e. the neutral 1-(2-(4-((2,2,2-tri(1H-pyrazol-1-yl)ethoxy)methyl)benzyloxy)-1,1-di(1H-pyrazol-1-yl)ethyl)-1H-pyrazole {p-C6H4[CH2OCH2C(pz)3]2, (L1), and the anionic hydridotris(3-phenyl-5-methylpyrazolyl)borate (L2)−, bis(pyrazolyl)acetate (L3) and bis(3,5-dimethylpyrazolyl)acetate (L4)−: the species [L1(CuCl2)2] (1), [L1(Cu(OAc)2)2] (2), [L1(Zn(OAc)2)2] (3), [(CuCl(L2)(HpzPh,Me)] (4), [Mn(L3)2]·2H2O, (5), [ZnCl(L3)(imH)]·MeOH [CuCl(L4)(imH)]·2H2O (7) have been obtained (HpzPh,Me =3-phenyl-5-methylpyrazole, imH=imidazole). Complexes 1 and 4 have been structurally characterized, also using less conventional powder diffraction methods. The superoxide scavenging activity has been characterized by indirect assays including EPR analysis. All complexes exhibit superoxide scavenging activity with IC50 in the µM range and they protect against the oxidative action of peroxynitrite in different ways. 1, 4 and 7 exert both an anti- and pro-oxidant effect depending on their concentration as evaluated by EPR and fluorescence methods. The pro-oxidative effects are absent in Zn(II) and Mn(II) complexes. [Copyright &y& Elsevier]

The salts [S(NMe2)3][MF6] (M = Nb, 2a; M=Ta, 2b) and [S(NMe2)3][M2F11] (M = Nb, 2c; M = Ta, 2d) have been prepared by reacting MF5 (M = Nb, 1a; M = Ta, 1b) with [S(NMe2)3][SiMe3F2] (TASF reagent) in the appropriate molar ratio. The solid state structure of 2b has been ascertained by X-ray diffraction. The 1:1 molar ratio reactions of 1a with a variety of organic compounds (L) give the neutral adducts NbF5L [L = Me2CO, 3a; L = MeCHO, 3b; L = Ph2CO, 3c; L = tetrahydrofuran (thf), 3d; L = MeOH, 3e; L = EtOH, 3f; L = HOCH2CH2OMe, 3g; L = Ph3PO, 3h; L = NCMe, 3i] in good yields. The complexes MF5L [M = Nb, L = HCONMe2, 3j; M = Nb, L = (NMe2)2CO, 3k; M = Ta, L = (NMe2)2CO, 3l; M = Nb, L = OC(Me)CH=CMe2, 3m] have been detected in solution in admixture with other unidentified products, upon 2:1 molar reaction of 1 with the appropriate reagent L. The ionic complexes [NbF4(tht)2][NbF6], 4a, and [NbF4(tht)2][Nb2F11], 4b, have been obtained by combination of tetrahydrothiophene (tht) and 1a, in 1:1 and 2:3 molar ratios, respectively. The treatment of 1 with a two-fold excess of L leads to the species [MF4L4][MF6] [M = Nb, L = HCONMe2, 5a; M = Ta, L = HCONMe2, 5b; M = Nb, L = thf, 5c; M = Ta, L = thf, 5d; M = Nb, L = OEt2, 5e]. The new complexes have been fully characterised by NMR spectroscopy. Moreover, the revised 19F NMR features of the known compounds MF5L [M = Ta, L = Me2CO, 3n; M = Ta, L = Ph2CO, 3o; M = Ta, L = MePhCO, 3p; M = Ta, L = thf, 3q; M = Nb, L = CH3CO2H, 3r; M = Nb, L = CH2ClCO2H, 3s; M = Ta, L = CH2ClCO2H, 3t], TaF4(acac), TaF4(Me-acac) and [TaF(Me-acac)3][TaF6] (Me-acac = methylacetylacetonato anion) are reported. [Copyright &y& Elsevier]

Abstract: A series of magnesium complexes of general formula [Mg(Tp x )2] (Tp x =Tp, Tp∗, Tp∗Cl, pzTp) and [Mg(Tp x )X] (X=Cl, Tp x =Tp t Bu or pz0Tp p -Tol; X=acetate, Tp x =Tp t Bu) were synthesised from magnesium chloride or acetate and M(Tp x ) (M=K, Na or Tl) in dichloromethane or alcoholic solution. These compounds are air-stable solids, sparingly soluble in most organic solvents; they have been characterized by elemental analysis, IR, 1H and 13C NMR spectra and, in selected cases, also by conductivity and molecular weight measurements. Single crystal X-ray diffraction studies of [Mg(Tp)2], [Mg(Tp*)2] and [Mg(Tp*Cl)2] show unsolvated neutral bis(tripod ligand)magnesium(II) molecules with six-coordinate magnesium atoms (〈Mg–N〉 2.167(6), 2.19(2), 2.205(4)Å). [Copyright &y& Elsevier]

Abstract: By heating a sample of Tb/Na tobermorite we obtained a phase which was identified through its X-ray diffraction (XRD) pattern, as terbium silicate apatite. Subsequently this compound has been directly prepared by solid state reaction and we carried out a structural refinement from XRD data in space group P63/m obtaining cell parameters a=9.39199(4)Å and c=6.84041(5)Å. Terbium silicate apatite heated in melted NaF led to Tb4O7 crystals. [Copyright &y& Elsevier]

The SPh functionalized vinyliminium complexes [Fe2{μ-η1:η3-Cγ(R′)=Cβ(SPh)Cα=N(Me)(R)}(μ-CO)(CO)(Cp)2][SO3CF3] [R = Xyl, R′ = Me, 2a; R = Me, R′ = Me, 2b; R = 4-C6H4OMe, R′ = Me, 2c; R = Xyl, R′ = CH2OH, 2d; R = Me, R′ = CH2OH, 2e; Xyl = 2,6-Me2C6H3] are generated in high yields by treatment of the corresponding vinyliminium complexes [Fe2{μ-η1:η3-Cγ(R′)=Cβ(H)CαN(Me)(R)}(μ-CO)(CO)(Cp)2][SO3CF3] (1a–e) with NaH in the presence of PhSSPh. Likewise, the diruthenium complex [Ru2{μ-η1:η3-Cγ(Me)=Cβ(SPh)Cα=N(Me)(Xyl)}(μ-CO)(CO)(Cp)2][SO3CF3] (2f) was obtained from the corresponding vinyliminium complex [Ru2{μ-η1:η3-Cγ(Me)=Cβ(H)Cα=N(Me)(Xyl)}(μ-CO)(CO)(Cp)2] (1f). The synthesis of 2c is accompanied by the formation, in comparable amounts, of the aminocarbyne complex [Fe2{μ-CN(Me)(4-C6H4OMe)}(SPh)(μ-CO)(CO)(Cp)2] (3).The molecular structures of 2d, 2e and 3 have been determined by X-ray diffraction studies. [Copyright &y& Elsevier]

The complexes MX5(THF) (M = Nb, X = CI, 2a; M = Ta, X = F, 2c, X = Cl, 2d) and [MX4(THF){O(CH2)4- (CH2)3CH2)}][MX6] (M = Nb, X = Cl, 3a; M = Ta, X = Cl, 3d, X = Br, 3e, X = I, 3f) result from reactions of MX5 with 0.5 and 1 .5 equiv of THF, respectively. Compounds 3 contain the unprecedented 4-(tetrahydrofuran-1-ium)-butan-1-oxo ligand and are likely to play a role in the course of THF polymerization catalyzed by MX5. The addition of L (L = 2,5-dimethyltetrahydrofuran, tetrahydropyran, 1 ,4-dioxane) to MX5 results in the formation of the hexacoordinated complexes MX5(L). The molecular structures of 2d, 3d, and NbCI5(dioxane), 6a, have been ascertained by X-ray diffraction studies. [ABSTRACT FROM AUTHOR]

The metal halides of Group 5 MX5 (M = Nb, Ta; X = F, Cl, Br) react with ketones and acetylacetones affording the octahedral complexes [MX5(ketone)] (2a-j) and [TaX4{κ2(O)-OC(Me)C(R)C(Me)O}] (R = H, Me, 5a-e), respectively. The adducts [MX5(acetone)] are still reactive towards acetone, acetophenone or benzophenone, giving the aldolate species [MX4{κ2(O)-OC(Me)CH2C(R)(R′)O}] (3a-e). The syntheses of 3b (M = Ta, X = F, R = R′ = Ph) and 3d (M = Ta, X = Cl, R = Me, R′ = Ph) take place with concomitant formation of [(Ph2CO)2-H][TaF6], 4a, and [(MePhCO)2-H][TaCl6], 4b, respectively. The compounds [acacH2][TaF6], 6, and [TaF{OC(Me)C(Me)C(Me)O}3][TaF6], 7, have been isolated as by-products in the reactions of TaF5 with acacH and 3-methyl-2,4-pentanedione, respectively. The molecular structures of 2i, 3c, 4a, 4b and 7 have been ascertained by single crystal X-ray diffraction studies. [ABSTRACT FROM AUTHOR]

Abstract: The bridging diiron thiocarbyne complex [Fe2{μ-CS(Me)}(μ-CO)(CO)2(Cp)2][SO3CF3] (1) reacts with activated olefins (methyl acrylate, acrylonitrile, styrene, diethyl maleate), in the presence of Me3NO and NaH, to give the corresponding μ-allylidene complexes [Fe2{μ-η1:η3-Cα(SMe)Cβ(R′)Cγ(H)(R″)} (μ-CO)(CO)(Cp)2] (R″=CO2Me, R′=H, 3a; R″ = CN, R′=H, 3b; R″=C6H5, R′=H, 3c; R″=R′=CO2Et, 3d). The coupling reaction of olefin with thiocarbyne is regio- and stereospecific, leading to the formation of only one isomer. C–C bond formation occurs between the less substituted alkene carbon and the thiocarbyne. Moreover, olefinic hydrogens of the bridging ligands are mutually trans. The reactions of 3a–b with MeSO3CF3 result, selectively, in the formation of the cationic μ-sulphonium allylidene complexes [Fe2{μ-η1:η3-Cα(SMe2)Cβ (H)Cγ(H)(R)}(μ-CO)(CO)(Cp)2][SO3CF3] (R=CO2Me, 4a; R=CN, 4b). Compound 4a undergoes displacement of the SMe2 group by nucleophiles such as NaBH4, NBu4CN and NaOMe, affording the complexes [Fe2{μ-η1:η3-Cα(R)Cβ (H)Cγ(H)(CO2Me)}(μ-CO)(CO)(Cp)2] (R=H, 5a; R=CN, 5b; R=OMe, 5c), respectively. The molecular structures of 3a and 5a have been determined by X-ray diffraction studies. [Copyright &y& Elsevier]

The syntheses of haloacetates of iron(II) and their reactivity are described. The compound Fe(CF3COO)2, 1, crystallizes from CF3COOH/(CF3CO)2O solution as the polynuclear [Fe(CF3COO)2(CF3COOH)2]n, 2, which contains bridging trifluoroacetates and monodentate trifluoroacetic acid groups. Fe(CF3COO)2(DMF)x, as obtained from Fe(CO)5 and CF3COOH/(CF3CO)2O in DMF, reacts with dioxygen at room temperature to give two μ3-oxo compounds, namely, [Fe3(μ3-O)(CF3COO)6(DMF)3], 3, a Fe(II)-Fe(III)-Fe(III) derivative, and [Fe4(μ3-O)2(μ2-CF3COO)6(CF3COO)2(DMF)4], 4, containing Fe(III) atoms only, which have been characterized by X-ray diffraction methods. lron(II) chloro- and bromoacetates can be isolated by exchange reactions of iron(II) acetate with chloro- and bromo-substituted acetic acids in moderate to good yields. The stability of iron(ll) haloacetates decreases on increasing the atomic weight and the number of halogens on the α-carbon atom. The species Fe(CX3COO)2 (X = Cl, 7; Br, 8), in THF solution, slowly convert into [Fe3(μ3-O)(CCl3COO)6(THF)3], 11, or [Fe3(μ3-O)(CBr3COO)6(THF)3][FeBr4], 10, respectively. Likewise, when iron(II) acetate (or trifluoroacetate) is left for several hours in the presence of a variety of haloacetic acids in THF, selective formation of different species, depending on the nature of the starting compound and of the acid employed, is observed. The formation of these products is the result of C-X bond activation (X = Cl, Br) and haloacetato decomposition, which occurs with concomitant oxidation at the metal centers. Carboxylic acid degradation species (CH2XCOOH, CX4, CX3H, CX2H2, X = Cl, Br) have been observed by GC·MS. [ABSTRACT FROM AUTHOR]

Abstract: Ten novel adducts of the form AgClO4:PR3:L (1:1:1) (R=Ph, cy, o-tolyl; L=2,2′-bipyridyl (‘bpy’), 2,2′-biquinoline (‘bq’), bis(2-pyridyl)amine (‘dpa’), bis(2-picolyl)amine (‘dpca’)) have been synthesized and characterized by analytical, spectroscopic (IR, far-IR, 1H and 31P NMR) and single crystal X-ray diffraction studies. The solid state molecular structures show that the complexes predominantly take the form [(R3P)AgL]+X−, with a trigonal PAgN2 coordination environment, where the approach of the anion or the solvent may perturb the planarity of the silver environment. The ClO4 anion shows uni- or semi-bidentate coordination, except in the complexes AgClO4:PR3:dpca (1:1:1) (R=Ph and o-tolyl), where the anion remains uncoordinated and the dpca donor is a three-coordinate pincer-like ligand. [Copyright &y& Elsevier]

Correction for ‘Self-assembly of arene ruthenium acylpyrazolone fragments to tetranuclear metallacycles. Molecular structures and solid-state 15N CPMAS NMR correlations’ by Riccardo Pettinari et al., Dalton Trans., 2016, 45, 3974–3982. [ABSTRACT FROM AUTHOR]

Abstract: Syntheses, spectroscopic characterization and single crystal X-ray studies are reported for a number of complexes of copper(II) salts with simple monodentate nitrogen bases. The 1:4 adduct of copper(II) sulfate with 3,5-dimethylpyridine (m2py) CuSO4·4m2py, takes the form [(O3SO)Cu(m2py)4], the Cu–O vector of the square–pyramidal coordination environment being disposed on the 4-axis in tetragonal space group P4/n. The complex CuCO3·Cu(NCS)2·4py is a linear polymer, taking the form ⋯O·Cu(py)2·O·C{O·Cu(py)2(NCS)2}·O·Cu(py)2⋯ (etc.), all atoms lying in the mirror plane of space group Pnma, excepting the pair of ‘py’ (pyridine) ligands disposed to either side. In Cu(OH)I·3/4I2·2py·1/2MeCN≡[{(py)2Cu(OH)}4](I3)3I·2MeCN a novel cubanoid tetranuclear cation is found (2-symmetry). The EPR spectra of the above compounds show a trend in the anisotropy of the g-values that correlates well with the crystal structures. Obtained only in small quantities but supported by single crystal X-ray studies are the adduct of Cu(OH)Cl with pyrrolidine (pyrr), Cu(OH)Cl:pyrr (1:3), which takes the centrosymmetric binuclear form [(pyrr)3Cu(μ-OH)2Cu(pyrr)3]Cl2, the copper atom being disposed in a distorted trigonal bipyramidal array, and the adduct 3CuCl2·CuO·4quin, [Cu4Cl6O(quin)4]Cl2, which contains the familiar Cu4Cl6O core with monodentate quinuclidine (quin) attached to the copper atoms; this compound crystallizes in the cubic space group . [Copyright &y& Elsevier]

Abstract: In this review we summarize some recent literature data concerning synthetic procedures, properties, structure, reactivity and applications of halo-carbonyl complexes of palladium, platinum and gold, taking into consideration that the organometallic chemistry of these metals, with a particular attention to the halo-carbonyls, has been reviewed 20 years ago [F. Calderazzo, J. Organomet. Chem. 400 (1990) 303]. A brief overview of the early studies is provided. [Copyright &y& Elsevier]

Previously reported structure-activity relationships have shown two features for effective antitumor activity of titanium β-diketone complexes: (a) ligand asymmetry and (b) the presence of planar substitutents on the ligand. Mono- and dinuclear derivatives, studied with diffraction and DFT methods show that (a) is consistent with different Ti-O(β-diketonato) bond lengths, which are longer than Ti-O(oxo) and Ti-O(alkoxy) ones. π-π features observed in dinuclear derivatives correlate with strong reactivity of related complexes with DNA and support DNA intercalation by such planar groups, in agreement with (b). Large variation for Ti-O bond lengths and Ti-O-C bond angles in the ethoxy moiety is associated with the titanium withdrawing effect and oxygen bonding s character; it is confirmed through exploration of the Cambridge crystallographic database. This ethoxy geometrical flexibility also suggests versatile accommodation in protein pockets and/or other biological targets. Electrospray ionization mass spectrometry (ESI-MS) spectra show formation of di- and trinuclear Ti-4-acyl-5-pyrazolonato cationic oligomers. Hydrolysis/oligomerization is also described by NMR results. [ABSTRACT FROM AUTHOR]

Abstract: The potassium and thallium(I) derivatives of the hydrido-tris(3-Me2Bz,5-Me-pyrazol-1-yl)borato ligand, K[TpMe2Bz,Me] (1) and Tl[TpMe2Bz,Me] (2), are reported. Their reactions with TiCl4 under mild conditions afforded, after rearrangement of the ligand, recognized as a double 1,2-borotropic shift, the related Ti(IV) complex {hydrido-[bis(3-Me,5-Me2Bz)(3-Me2Bz,5-Me)-pyrazol-1-yl]borato}trichlorotitanium(IV), [TpMe2Bz,Me∗∗] TiCl3 (3). The 1H- and 13C NMR spectra of the new compounds are discussed, the molecular structure of 3 has been determined by X-ray diffraction methods, the titanium centre has a pseudo-octahedral coordination, with the nitrogen and chloride ligands in a fac geometry. A possible mechanism of formation of 3 is proposed. [Copyright &y& Elsevier]

• Cyclopentadienyl iron complexes with a range of isocyanide ligands have been synthesized and characterized. • The reactions with methyl triflate proceed with abstraction of the iodide ligand rather than isocyanide alkylation. • The complexes are catalytically active in the ring opening polymerization of rac -lactide. Complexes [FeCpI(CO)(CNR)] [ 2a-f ; R = 2,6-C 6 H 3 Me 2 = Xyl, 4-C 6 H 4 OMe, CH 2 Ph, CH 2 P(O)(OEt) 2 , CH 2 SO 2 (4-C 6 H 4 Me), Me; Cp = η5-C 5 H 5 ] and [FeCpI(CNR) 2 ] [ 3a-f ; R = Xyl, 4-C 6 H 4 OMe, CH 2 Ph, CH 2 P(O)(OEt) 2 , Me] were obtained in 58-73% yields from the thermal reactions of [FeCpI(CO) 2 ] (1) in toluene with one/two equivalents of CNR, respectively, in the presence of [Fe 2 Cp 2 (CO) 4 ] as catalyst. The 1:2 molar reaction of 1 with CNMe resulted in the prevalent formation of [FeCp(CO)(CNMe) 2 ]I, 4f (86% yield). The reactions of 1 and 3a-c with an excess of CF 3 SO 3 CH 3 afforded the triflate adducts [FeCp(OSO 2 CF 3)L 2 ] (L = CO, 1TF ; Xyl, 3aTF ; 4-C 6 H 4 OMe, 3bTF ; CH 2 Ph, 3cTF), in 62-78% yields, via CH 3 I elimination. All products were characterized by elemental analysis, IR and multinuclear NMR spectroscopy, moreover the molecular structures of 2a, 2e and 3a were ascertained by single crystal X-ray diffraction. The potential of 1, 2a-f and 3a-f as catalysts in the bulk polymerization of rac -lactide was examined. [Display omitted] [ABSTRACT FROM AUTHOR]

Several mono- or bis-alkynyl derivatives of general formula Pt6(μ-PBut2)4(CO)4X(C≡C–R), Pt6(μ-PBut2)4(CO)4(C≡C–R)2 or Pt6(μ-PBut2)4(CO)4(C≡C–R)(C≡C–R′) were obtained under Sonogashira type conditions. The new clusters have been characterized with microanalysis and using IR and multinuclear NMR spectroscopy. The crystal and molecular structures of Pt6(μ-PBut2)4(CO)4(C≡C–R)2 (R = H, C6H4-4-n-C5H11) are presented and electrochemical and spectroelectrochemical studies of some representative compounds are also reported. [ABSTRACT FROM AUTHOR]

The propen-2-yl-dimetallacyclopentenone complex [Fe2Cp2(CO)(μ-CO){μ-η1:η3-Cα(H)＝Cβ(Cγ(CH3)CH2)C(＝O)}] (1) underwent electrophilic additions at the propenyl moiety to afford the μ-allenyl complexes [Fe2Cp2(CO)2(μ-CO){μ-η1:η2α,β-CαH＝CβCγ(CH3)(CH2E)}][BF4] (E = CPh3, [2][BF4]; E = H, [3][BF4]), in ca. 85% yield. The molecular structure of ([2][BF4]) was ascertained by X-ray diffractometry; X-ray, NMR and DFT results agreed in that one single isomer formed, bearing the [CH2CPh3] group pointing far from the Fe–Fe axis. The reaction of [3][BF4] with NHEt2 in the presence of PhSSPh resulted in the prevalent formation of [FeCp(CO)2SPh] (7). [ABSTRACT FROM AUTHOR]

Abstract: New (Q)2SnR2 derivatives (HQ in general; in detail: =4-diphenylacetyl-3-methyl-1-phenyl-5-pyrazolone; HQBn =3-methyl-1-phenyl-4-phenylacetyl-5-pyrazolone; HQnaph =3-methyl-4-naphthoyl-1-phenyl-5-pyrazolone; R=CH3, C2H5, C6H11, n- and t-C4H9, C6H5,) have been synthesised and characterised by analytical and spectral techniques. Variable temperature NMR studies of derivatives (R=CH3 and C2H5) in chlorohydrocarbon solvents indicate a fluxional behaviour, with rapid interconversion between six- and five-coordinate species, the latter containing a bidentate acylpyrazolonate and a monodentate one. The X-ray crystal structures of the diorganotin(IV) derivatives , , (QBn)2SnMe2 and , inclusive of a representative of each Q x family, show the metal centres in a skewed trans octahedral configuration. The 4-acyl moiety of the β-diketonate donor exerts a steric effect which is correlated to structural behaviour in the solid and solution state. A solid state 119Sn CPMAS NMR study of the (QBn)2SnR2 (R=CH3, C2H5, t-C4H9 and C6H5) complexes shows a marked deshielding effect and upfield movement of the 119Sn isotropic chemical shift (δ iso) through this series. The 119Sn chemical shift spans (Ω) are the largest reported for directly oxo-coordinated Sn(IV) systems, although the markedly reduced Ω value for the (QBn)2SnPh2 complex may be indicative of a cis octahedral coordination, in contrast to the trans octahedral coordination characterising the other complexes of this suite. [Copyright &y& Elsevier]

Abstract: Magnesium oxide reacts with dimethylammonium dimethylcarbamate, [Me2NH2][O2CNMe2], in toluene yielding the carbonato-carbamato complex [Me2NH2]3[Mg8(CO3)2(O2CNMe2)15] 1, which gradually loses [Me2NH2][O2CNMe2] upon mild heating or by lowering the carbon dioxide pressure to give products of intermediate composition [Me2NH2]n[Mg8(CO3)2(O2CNMe2)12+n] with n ranging from 3 to 0, the neutral complex [Mg8(CO3)2(O2CNMe2)12], 2, being obtained upon exhaustive treatment in vacuo. The equilibria may be shifted back from 2 to 1 by using an excess of [Me2NH2][O2CNMe2]. The same products were obtained in low yields by reacting magnesium with [Me2NH2][O2CNMe2]: in this case the reaction proceeds slowly, being presumably promoted by the presence of some MgO and/or H2O. The crystal and molecular structure of 1 has been studied by single-crystal X-ray diffraction methods, the anion containing a ring of eight edge- or apex-sharing {MgO6} distorted octahedra, with Mg–O distances in the range from 1.921 to 2.313 Å. The framework is kept together by two μ6-carbonato ligands and by the fifteen carbamato ligands. The ionic aggregates [NH2Me2]3[Mg8(CO3)2(OCONMe2)15] are alternated in the crystal with heptane molecules and only weak van der Waals interactions are present between adjacent octanuclear aggregates, in agreement with the solubility of the substance in toluene. To cite this article: D. Belli Dell''Amico et al., C. R. Chimie 7 (2004). [Copyright &y& Elsevier]

The long-time known reactivity of [Fe 2 Cp 2 (CO) 4 ] with isocyanides has been revisited with the aim of preparing, isolating and structurally characterizing the mono-substituted products. [Display omitted] • Good yields of [Fe 2 Cp 2 (CO) 3 (CNR)] have been obtained from [Fe 2 Cp 2 (CO) 4 ] and isocyanides. • The use of a molar excess of the diiron reactant avoids polysubstitution. • The coordination mode of the isocyanide is scarcely influenced by the environment. The reactions of [Fe 2 Cp 2 (CO) 4 ] with a series of isocyanides, CNR, were conducted in acetonitrile and afforded, after a thermal treatment, the mono-isocyanide derivatives [Fe 2 Cp 2 (CO) 3 (CNR)] [R = 1H-indol-5-yl, 1 ; CH 2 P(O)(OEt) 2 , 2 ; Cy = C 6 H 11 , 3 ; 4-C 6 H 4 OMe, 4 ; Xyl = 2,6-C 6 H 3 Me 2 , 5 ; Me, 6 ; 2-naphthyl, 7 ; Bn = CH 2 Ph, 8 ]. In order to avoid multiple substitution, the diiron reactant was used in a molar excess with respect to the isocyanide (1.6 equivalents; 1.1 for the synthesis of 8). The products were separated from unreacted [Fe 2 Cp 2 (CO) 4 ] by chromatography or via reversible protonation, and finally isolated in 50–83% yields. IR and NMR spectroscopy indicate that the isocyanide ligand is bridging coordinated in 2 and 7 , terminal in 3 and 5 , while in the remaining cases a mixture of terminal- and bridging-CNR isomers is obtained. The molecular structure of 5 was ascertained by X-ray diffraction. In general, the coordination mode of the isocyanide is scarcely influenced by the environment (solvents with different polarities, solid state). Sluggish partial isocyanide migration from terminal to bridging position was recognized for 3 and 5 upon heating in refluxing toluene, a process which was reproduced by DFT calculations. [ABSTRACT FROM AUTHOR]

Abstract: Rh2(cod)2(μ2-dppm)(μ2-Cl)]BF4 (1) rearranges under carbon monoxide to give [Rh3(μ2-dppm)2(μ2-CO)3(K 1-CO)3]BF4 (2). Complex 2 has been structurally characterized by single crystal X-ray crystallography. The hydroformylation activities of 1 and 2 were compared for substrates styrene and 1-hexene and the activity of 2 found to be unexpectedly high. [Copyright &y& Elsevier]

New pyridinimino complexes of platinum(II) [PtCl 2 (N^N-R)] (N^N = 2-pyridylmethanimino, R = -(CH 2) 2 O(CH 2) 2 OH, -(CH) 2 O(CH 2) 2 OCH 2 Pyr), Pyr = pyren-1-yl) have been prepared. They are characterized by a dioxygenated alkyl side chain and, in one case, by a fluorescent terminal 1-pyrenyl residue. The complexes were characterized by elemental analysis, IR, 1H–, 13C–and 195Pt NMR spectroscopies. For [PtCl 2 (N^N-(CH 2) 2 O(CH 2) 2 OH] the molecular structure was determined by single crystal X-ray diffraction. The complexes are soluble and stable in DMSO/H 2 O (80/20, v/v). The pyrenyl terminated compound was tested as antiproliferative agent against selected human cancer cell lines. Comparable cytotoxic effect was obtained on human ovarian carcinoma A-2780 and A-2780cis cells, thus suggesting a certain ability to circumvent cisplatin resistance. The interaction of this complex with DNA was investigated by linear flow dichroism and by spectrophotometric (absorbance and fluorescence) titrations. Both techniques enlightened the presence of a complex mode of interaction with DNA, involving both groove binding and intercalation. DNA interaction of a fluorescent, cytotoxic pyridinimino platinum(II) complex. Riccardo Bondi, Tarita Biver, Lisa Dalla Via, Federica Guarra, Mariafrancesca Hyeraci, Claudia Sissi, Luca Labella, Fabio Marchetti and Simona Samaritani. A versatile pyridinimino Pt(II) complex, bearing a pyrenyl-terminated side chain was synthesized. The complex circumvents cisplatin resistance towards A2780cis cells and is able to interact with DNA by both groove binding and intercalation. Unlabelled Image • A fluorescently tagged, cytotoxic pyridinimino platinum(II) complex was prepared. • The complex circumvents cisplatin resistance against A2780cis cancer cell line. • Complex/DNA interaction was studied by independent spectroscopic techniques. • DNA interaction takes place by both groove binding and intercalation. [ABSTRACT FROM AUTHOR]