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Ionic platinum(II) complexes [PtCl(PPh 3 )(L∧L)][BF 4 ] {L∧L = 2,2′-bipyridyl ( 1 ) 1,10-phenanthroline ( 2 )} and [PtCl(PPh 3 )(L) 2 ][BF 4 ] {L = pyridine ( 3 ), dimethyl sulfoxide ( 4 )} were synthesized by dehalogenation of cis- [PtCl 2 (PPh 3 )(NCMe)], followed by reaction with the suitable ligand. Chelating nitrogen ligands L∧L afforded single products, which were structurally characterized. In the other cases mixtures of geometric (L = pyridine) and/or coordination (L = dimethyl sulfoxide) isomers were observed in solution. In these cases the structures of the less soluble isomers were obtained via single crystal X-ray diffraction. All the complexes were tested in vitro for their antiproliferative activity on three human tumor cell lines: MSTO-211H, HeLa and HepG2. [ABSTRACT FROM AUTHOR]

Abstract: Fast oxidations of the iron(II) N,N-dialkylcarbamato complexes [Fe(II)(O2CNR2)2] n (R=Et, n =6, 1; R= i Pr, 2) and [Fe(II)8(μ4-O)2(O2CNiPr2)12], 3, by dioxygen were carried out both in an anhydrous hydrocarbon and in the solid state affording [Fe(III)2(O)(O2CNR2)4] x , 7 and 8 for R=Et and i Pr, respectively, and [Fe(III)4(O)3(O2CNiPr2)6] y , 9. The stoichiometric O2 uptake was not accompanied by oxidation of the ligand. Recovery of unchanged starting material was observed when the manganese(II) derivatives [Mn(II)(O2CNR2)2] n (R=Et, n =6, 4; R= i Pr, 5) were treated with O2. Nevertheless, when [Mn(II)8(μ4-O)2(O2CNiPr2)12], 6, prepared in situ by reaction of 5 with water (Mn/H2O molar ratio=4), was reacted with O2, complete oxidation occurred to a product where manganese showed an average oxidation number III, [Mn(III)4(O)3(O2CN i Pr2)6] y , 10. The product [Mn(II)6Mn(III)2(μ4-O)2(μ3-O)(O2CN i Pr2)12], 11, obtained by partial oxidation of 6 by O2, has been characterised by X-ray diffraction methods. [Copyright &y& Elsevier]

Dinuclear platinum(II) complexes [{PtCl 2 (PPh 3 )} 2 (μ-N–N)], where N–N is a divergent bidentate nitrogen ligand, were prepared by reacting cis -[PtCl 2 (PPh 3 )(NCMe)] with N–N in a Pt/N–N molar ratio 2. The ( trans , trans )-isomers were obtained as kinetic products and recovered in good yields and high purity { 1 , N–N = pyrazine (pyrz); 2 , N–N = 4,4′-bipyridyl (bipy); 3 , N–N = piperazine (pipz); 4 , N–N = p-xylylendiamine (xylN 2 )}. Cis -[PtCl 2 (PPh 3 )(NCMe)] was also reacted with the tridentate divergent ligand 2,4,6-tris-(pyrid-4′-yl)1,3,5-triazine (py3TRIA) in molar ratio 3 with formation of the trinuclear ( trans , trans , trans )-[{PtCl 2 (PPh 3 )} 3 (μ-py3TRIA)], 5 . On the other hand, the treatment of cis -[PtCl 2 (PPh 3 )(NCMe)] with the monodentate pyridine (py) produced a mixture of both trans -[PtCl 2 (PPh 3 )(py)] ( 6a ) and cis -[PtCl 2 (PPh 3 )(py)] ( 6b ). The reactions of cis -[PtCl 2 (PPh 3 )(NCMe)] with N–N = pyrz, bipy, pipz, carried out with a Pt/N–N molar ratio 1, were monitored by 31 P NMR spectroscopy. Equilibria were observed in solution, involving dinuclear ( trans – trans )-[{PtCl 2 (PPh 3 )} 2 (μ-N–N)], mononuclear [PtCl 2 (PPh 3 )(N–N)] and free N–N. The addition of an excess of the divergent ligand allowed the complete conversion to the corresponding mononuclear complexes. With the heteroaromatic ligands both geometric isomers were observed ( 7a , 7b and 8a , 8b , for pyrz and bipy derivatives, respectively) while with pipz the trans -isomer only was detected, 9 . In the system involving bipy, the scarcely soluble dinuclear ( cis , cis )-[{PtCl 2 (PPh 3 )} 2 (μ-bipy)], 2b , was also obtained. Products 2 , 2b , 3 ·2(CHCl 3 ) and 6a ·0.5(C 2 H 4 Cl 2 ) were structurally characterized by single crystal X-ray diffraction methods. [ABSTRACT FROM AUTHOR]

Partial hydrolysis (H 2 O/Ln molar ratio = ¼) of lanthanum di- iso -propylcarbamato complex, [La(O 2 CN i Pr 2 ) 3 ], 1 , afforded the tetranuclear μ-oxo derivative [La 4 O(O 2 CN i Pr 2 ) 10 ], 2 , which was structurally characterized by single crystal X-ray diffraction studies. The carbonato–carbamato derivative of lanthanum, [La 4 (CO 3 )(O 2 CNBu 2 ) 10 ], 3 , was prepared by extraction of lanthanum ions from aqueous solution into heptane by the NHBu 2 /CO 2 system. Partial hydrolysis (H 2 O/Ln molar ratio = ½) of N , N -di-iso-propylcarbamato complexes of neodymium, europium, gadolinium and terbium, [Ln(O 2 CN i Pr 2 ) 3 ], yielded the derivatives [Ln 2 (CO 3 )(O 2 CN i Pr 2 ) 4 ] (Ln = Nd, 4 , Eu, 5 , Gd, 6 ). Exhaustive hydrolysis of [Ln(O 2 CNR 2 ) 3 ] (Ln = Nd, Tb, R = Bu; Ln = Eu, Gd, R = i Pr, Bu) produced hydrated lanthanide carbonates, Ln 2 (CO 3 ) 3 · n H 2 O. For sake of comparison with a block d metal, the exhaustive hydrolysis of two copper(II) carbamato complexes, [Cu(O 2 CNEt 2 ) 2 (NHEt 2 )] 2 and [Cu(O 2 CN i Pr 2 ) 2 ], was carried out with formation in both cases of the hydrated basic carbonate Cu 2 (OH) 2 (CO 3 )· n H 2 O. The exhaustive hydrolysis of mixtures of cerium and lanthanum or cerium and terbium N , N -dibutylcarbamato complexes allowed the preparation of mixed oxides containing the two metals in the desired molar ratio, via the intermediate formation of the corresponding mixed carbonates. [ABSTRACT FROM AUTHOR]

A series of neutral complexes of platinum(II) of general formula [PtCl 2 L(PPh 3 )] [L = Et 2 NC(Me)NH, SOMe 2 , CO, Et 2 NH, (HOCH 2 CH 2 ) 2 NH, Bz 2 NH, N-morpholine] was prepared starting from suitable precursors. The syntheses and spectroscopic characterizations of the two new complexes trans -[PtCl 2 (N-morpholine)(PPh 3 )] and cis -[PtCl 2 (SOMe 2 )(PPh 3 )] are described as well as their X-ray structures. The antiproliferative activity of all the available compounds was tested in vitro against HeLa, H460 and A549 human tumor cell lines. A brief discussion regarding the structure–activity correlation is presented. [ABSTRACT FROM AUTHOR]

Neodymium and terbium pentafluorophenolates, containing 1,10-phenanthroline as ancillary ligand, [Ln(OC 6 F 5 ) 3 (phen) 3 ], ( 1 Ln = Nd, 2 Ln = Tb) have been synthesized by reacting the N , N -dibutylcarbamato complexes, [Ln(O 2 CNBu 2 ) 3 ], easily obtained from aqueous solutions of lanthanide salts, with C 6 F 5 OH in the presence of 1,10-phenanthroline. The formation of the sparingly soluble hydrated compound [Tb(OC 6 F 5 ) 3 (phen) 2 (H 2 O)·phen], 3 , was observed, due to fortuitous presence of water. Single crystal X-ray diffraction studies on compounds 1 , 3 and 3 ·DME (DME = dimethoxyethane) showed coordination numbers (CN) 9 for neodymium in 1 and 8 for terbium in 3 and 3 ·DME, where only two 1,10-phenanthroline ligands are coordinated to terbium, the third forming two hydrogen bonds with the coordinated water. The structural characterisation of [NH 2 Bu 2 ][C 6 F 5 O], 4 , showed the organisation of the product in ionic quartets. The photoluminescence spectra of 1 and 2 displayed the typical emissions related to the lanthanide centre in the NIR and visible region, respectively. [ABSTRACT FROM AUTHOR]