An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

The synthesis of the new palladium and platinum complexes with 9-methylhypoxanthine (9-mhypH) of the type [M(dmba)(L)(9-mhypH-N7)]ClO(4) [dmba = N,C-chelating 2-(dimethylaminomethyl)phenyl; M = Pd or Pt; L = DMSO, PPh(3) or PTA (PTA = 1,3,5-Triaza-7-phosphaadamantane)] is reported. Pd(II) and Pt(II) complexes with the anion of 9-mhypH of the type [M(dmba)(L)(9-mhyp-N1)] [L = PPh(3) or PTA] have also been prepared. The crystal structures of [Pt(dmba)(PPh(3))(9-mhypH-N7)]ClO(4) and [Pt(dmba)(PPh(3))(9-mhyp-N1)] have been established by X-ray diffraction. The last complex is the first structurally authenticated example of N1 coordination of 9-methylhypoxanthine to platinum. DFT-based calculations at the BP86/def2TZVP level predict a most favourable interaction (both kinetically and thermodynamically) of the metal(II) centre with N7 in the neutral ligand 9-mhypH, but with N1 in the deprotonated ligand 9-mhyp(-) in agreement with the experimentally observed preference in neutral conditions or upon basic treatment, respectively.

The reaction between Pd(dba)2 and phosphino-amide ligands yielded the unexpected Pd(II) homoleptic complexes [Pd(o-Ph2PC6H4CO-NR)2] [R=iPr (1), Ph (2), 4-MeC6H4 (3), 4-FC6H4 (4)], in which an κ2-P,N coordination mode for diphenylphosphine–benzamidate ligands is observed. In order to induce amide protonation in the ligands and subsequent κ2-P,O coordination, compounds (1-4) were treated with HClO4(aq) to give cationic complexes [Pd(o-Ph2PC6H4CO-NHR)2][ClO4]2 (5-8). These complexes and the analogous with iminophosphine ligands [Pd(o-Ph2PC6H4CHN-R)2] [ClO4]2 [R=iPr (9), Ph (10)] can be alternatively obtained when [PdCl2(PhCN)2] is treated with AgClO4 in the presence of the corresponding ligand. The reaction of Pd(dba)2 with iminophosphines has also been explored, yielding in this case the Pd(0) derivatives [Pd(o-Ph2PC6H4CHN-R)2] [R=iPr (11), Ph (12)]. X-ray structures of (3), (4), (5), (8) and (9) have been established, allowing an interesting comparative structural discussion.

The new complexes [Pd(dmba)(N10-9AA)(PPh3)]CIO4 (1), [Pt(dmba)(N9-9AA)(PPh3)]CIO4 (2), [Pd(dmba)(N10-9AA)Cl] (3), and [Pd(C6F5)(N10-9AA)(PPh3)Cl] (4) (9-AA = 9-aminoacridine; dmba = N,C-chelating 2-(dimethylaminomethyl)phenyl) have been prepared. The crystal structures have been established by X-ray diffraction. In complex 2, an anagostic C-H center dot center dot center dot Pt interaction is observed. All complexes are luminescent in the solid state at room temperature, showing important differences between the palladium and platinum complexes. Complex 2 shows two structured emission bands at high and low energies in the solid state, and the lifetimes are in agreement with excited states of triplet parentage. Density functional theory and time-dependent density functional theory calculations for complex 2 have been done. Values of IC50 were also calculated for the new complexes 1-4 against the tumor cell line HL-60. All of the new complexes were more active than cisplatin (up to 30-fold in some cases). The DNA adduct formation of the new complexes synthesized was followed by circular dichroism and electrophoretic mobility. Atomic force microscopy images of the modifications caused by the complexes on plasmid DNA pBR322 were also obtained.

Palladium and platinum complexes with HmtpO (where HmtpO=4,7-dihydro-5-methyl-7-oxo[1,2,4]triazolo[1,5-a]pyrimidine, an analogue of the natural occurring nucleobase hypoxanthine) of the types [M(dmba)(PPh3)(HmtpO)]ClO4[dmba=N,C-chelating 2-(dimethylaminomethyl)phenyl; M=Pd or Pt], [Pd(N-N)(C6F5)(HmtpO)]ClO4[N-N=2,2'-bipyridine (bpy), 4,4'-dimethyl-2,2'-bipyridine (Me2bpy), or N, N, N', N'-tetramethylethylenediamine (tmeda)] and cis-[M(C6F5)2(HmtpO)2] (M=Pd or Pt) (head-to-head atropisomer in the solid state) have been obtained. Pd(II) and Pt(II) complexes with the anion of HmtpO of the types [Pd(tmeda)(C6F5)(mtpO)], [Pd(dmba)(micro-mtpO)] 2, and [NBu4]2[M(C6F5)2(micro-mtpO)]2(M=Pd or Pt) have been prepared starting from the corresponding hydroxometal complexes. Complexes containing simultaneously both the neutral HmtpO ligand and the anionic mtpO of the type [NBu4][M(C6F5)2(HmtpO)(mtpO)] (M=Pd or Pt) have been also obtained. In these mtpO-HmtpO metal complexes, for the first time, prototropic exchange is observed between the two heterocyclic ligands. The crystal structures of [Pd(dmba)(PPh 3)(HmtpO)]+, cis-[Pt(C6F5)2(HmtpO)2].acetone, [Pd(C6F5)(tmeda)(mtpO)].2H2O, [Pd(dmba)(micro-mtpO)]2, [NBu4]2[Pd(C6F5)2(micro-mtpO)]2.CH2Cl2.toluene, [NBu4]2[Pt(C6F5)2(micro-mtpO)](2).0.5(toluene), and [NBu4][Pt(C6F5)2(mtpO)(HmtpO)] have been established by X-ray diffraction. Values of IC50 were calculated for the new platinum complexes cis-[Pt(C6F5)2(HmtpO)2] and [Pt(dmba)(PPh3)(HmtpO)]ClO4 against a panel of human tumor cell lines representative of ovarian (A2780 and A2780 cisR), lung (NCI-H460), and breast cancers (T47D). At 48 h incubation time, both complexes were about 8-fold more active than cisplatin in T47D and show very low resistance factors against an A2780 cell line, which has acquired resistance to cisplatin. The DNA adduct formation of cis-[Pt(C6F5)2(HmtpO)2] and [Pt(dmba)(PPh3)(HmtpO)]ClO4 was followed by circular dichroism and electrophoretic mobility. Atomic force microscopy images of the modifications caused by these platinum complexes on plasmid DNA pB R322 were also obtained.

The dinuclear hydroxo complex [{Pd(μ-OH)(Phox)}2] (I) (Phox = 2-(2-oxazolinyl)phenyl) reacts in a 1:2 molar ratio with several imidate ligands to yield new cyclometallated palladium complexes [{Pd(μ-NCO)(Phox)}2] containing asymmetric imidate –NCO– bridging units. [–NCO– = succinimidate (succ) (1), phtalimidate (phtal) (2), maleimidate (mal) (3), 2,3-dibromomaleimidate (2,3-diBrmal) (4) and glutarimidate (glut) (5)]. The reaction of these complexes with tertiary phosphines provides novel mononuclear N-bonded imidate derivatives of the general formula [Pd(imidate)(Phox)(PR3)] [R = Ph (a), 4-F–C6H4 (b) or CH2CH2CN (c)]. The new complexes were characterized by partial elemental analyses and spectroscopic methods (IR, FAB, 1H, 13C and 31P). The single-crystal structures of compounds 4, 4a and 5a have been established.

The dinuclear hydroxo complexes [{Pd(mu-OH)(C boolean AND N)}(2)] [C boolean AND N = 2-(2-pyridyl)phenyl (Phpy) (I), 7,8-benzoquinolyl (Bzq) (II) and 2-(2-oxazolinyl)phenyl (Phox) (III)] react in a 1:2 molar ratio with a wide variety of erotic electrophiles H(L boolean AND L) bearing different sets of donor atoms (L boolean AND L = O boolean AND O or O boolean AND N) to give the mononuclear neutral palladium(II) derivatives with the general formula [Pd(L boolean AND L)(C boolean AND N)] [O boolean AND O = salicylaldehydate (sal) (1), acetylacetonate (acac) (2) and benzoylacetonate (bzac) (3); O boolean AND N = N-phenylsalicylaldiminate (N-Phsal) (4), N-p-chlorophenylsalicylaldiminate (N-pClPhsal) (5), 2-pyrrole-carbaldeydate (2-pcal) (6), 8-hydroxyquinolinate (oxin) (7)]. Structural characterisation of complexes I1, I3, I6, II4, II5 and III5 by X-ray diffraction confirmed the proposed formulae. Dinuclear complexes [{Pd(mu-N boolean AND S)(C boolean AND N)}(2)] [N boolean AND S = 2-pyridinethiolate (spy)] (8) were obtained when treating complexes I-III with 2-mercaptopyridine in the same molar ratio. A related process takes place when the three precursors react with ammonium O,O'-diethyldithiophosphate under mild conditions and complexes [Pd{S(S)P(OEt)(2)}(C boolean AND N)] (I9-III9) are obtained. Deprotonation of the secondary amine Et2NH by complexes I-III in the presence of carbon disulfide leads to the corresponding dithiocarbamate complexes [Pd(S2CNEt2)(C boolean AND N)] (I10-III10). The new complexes were characterised by analytical and spectroscopic techniques (IR and H-1 NMR). ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

The reaction of [Pt(dmba)(PPh3)Cl] [where dmba = N,C-chelating 2-(dimethylaminomethyl)phenyl] with aqueous ammonia in acetone in the presence of AgClO4 gives the acetonimine complex [Pt(dmba)(PPh3)(NH=CMe2)]ClO4 (1). The reaction of [Pt(dmba)(DMSO)Cl] with aqueous ammonia in acetone in the presence of AgClO4 gives a mixture of (Pt(dmba)(NH=CMe2)(2)]ClO4 (2) and [Pt(dmba)(imam)]ClO4 (3a) (where imam = 4-imino-2-methylpentan-2-amino). [Pt(dmba)(DMSO)Cl] reacts with [Ag(NH=CMe2)(2)]ClO4 in a 1:1 molar ratio to give [Pt(dmba)(DMSO)(NH=CMe2)]ClO4 (4). The reaction of [Pt(dmba)(DMSO)Cl] with 20% aqueous ammonia in acetone at 70 degrees C in the presence of KOH gives [Pt(dmba)(CH2COMe)(NH=CMe2)] (5), whereas the reaction of [Pt(dmba)(DMSO)Cl] with 20% aqueous ammonia in acetone in the absence of KOH gives [Pt(dmba)(imam)]Cl (3b). The reaction of (NBu4](2)[Pt-2(C6F5)(4)(mu-Cl)(2)] with [Ag(NH=CMe2)(2)]ClO4 in a 1:2 molar ratio produces cis-[Pt(C6F5)(2)(NH=CMe2)(2)] (6). The crystal structures of 1 . 2Me(2)CO, 2, 3a, 5, and 6 have been determined. Values of IC50 were calculated for the new platinum complexes against a panel of human tumor cell lines representative of ovarian (A2780 and A2780cisR) and breast cancers (T47D). At 48 h incubation time complexes 1, 4, and 5 show very low resistance factors against an A2780 cell line which has acquired resistance to cisplatin. 1, 4, and 5 were more active than cisplatin in T47D (up to 30-fold in some cases). The DNA adduct formation of 1, 4, and 5 was followed by circular dichroism and electrophoretic mobility.

The syntheses and crystal structures of the first examples of an anionic 1-methylthymine [deprotonated at the endocyclic NH group N(3)] acting as a chelating ligand for the cis-Pd(C6F3H2)2 and cis-Pd(C6F5)2 moieties through N(3) and O(4) are reported.

Substituted-benzoate complexes of nickel(II) of the types bidentate [Ni(mcN3)(Bz)](PF6) and monodentate [Ni(mcN3)(Bz)(H2O)](PF6) have been prepared by acid-base reaction between the hydroxo complexes [Ni(mcN3)(μ-OH)]2(PF6)2 (mcN3=2,4,4-trimethyl-1,5,9-triazacyclododec-1-ene (Me3-mcN3) or its 9-methyl derivative (Me4-mcN3)) and the corresponding benzoic acid. The paramagnetic nickel(II) complexes have been characterized in solution by NMR spectroscopy. The influence of the substituents on the hyperfine shift patterns for substituted-benzoate complexes of nickel(II) has been studied. The substituent effects upon the coordination mode of substituted benzoates have been established by X-ray diffraction.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

The dimeric starting material [Ru(η6-p-cymene)(μ-Cl)Cl]2 reacts with the phosphino-amides o-Ph2P–C6H4CO–NH–R [R = iPr (a), Ph (b), 4-MeC6H4 (c), 4-FC6H4 (d)] to give the mononuclear compounds 1a–d [RuCl(η6-p-cymene)(o-Ph2P–C6H4–CO–NH–R)]Cl. The subsequent reaction of these complexes with KPF6 produced the cationic species 2a–d [RuCl(η6-p-cymene)(o-Ph2P–C6H4–CO–NH–R)][PF6] in which phosphino-amides also act as rigid P,O-chelating ligands. The molecular structures of 2b–d were determined crystallographically. Amide deprotonation is achieved when complexes 2a–d were made react with 1 M aqueous solution of KOH, affording the corresponding neutral species 3a–d [RuCl(η6-p-cymene)(o-Ph2P–C6H4–CO–N–R)] in which a P,N-coordination mode is suggested.

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An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Contrary to common belief a single C-H center dot center dot center dot F-C contact in [(eta(5)-C5H5) Pd(C6F5)(PPh3)] is strong enough to pair two independent molecules and render them crystallographically different as suggested by its strongest H-1 - F-19 dipole - dipole coupling in a 2-D CP/MAS PILGRIM NMR experiment together with solid state 1-D F-19{H-1} and 2-D F-19 RFDR NMR spectroscopy - thereby proving the power of 2-D solid-state NMR for assessing the strength of supramolecular contacts.

The monomeric complex [Pd(dmba) Cl(PTA)] [dmba = N,C-chelating 2-(dimethylaminomethyl) phenyl; PTA = 1,3,5-triaza-7-phosphaadamantane] has been obtained and its crystal structure has been established by X-ray diffraction. Conditions for an efficient copper-and amine-free catalyzed Sonogashira reaction of aryl bromides and chlorides with terminal alkynes by [Pd(dmba)Cl(PTA)] and Pd(OAc)(2)/PTA have been developed. It is worthwhile noting that a relatively low palladium catalyst loading has been employed.

Contrary to common belief a single C–H⋯F–C contact in [(η5-C5H5)Pd(C6F5)(PPh3)] is strong enough to pair two independent molecules and render them crystallographically different as suggested by its strongest 1H–19F dipole–dipole coupling in a 2-D CP/MAS PILGRIM NMR experiment together with solid state 1-D 19F{1H} and 2-D 19F RFDR NMR spectroscopy – thereby proving the power of 2-D solid-state NMR for assessing the strength of supramolecular contacts.

CO2 and HCO3- react with the dinuclear hydroxo-complex [Ni(mcN3)(mu-OH)]2(PF6)2 (mcN3 = 2,4,4,9-tetramethyl-1,5,9-triazacyclododec-1-ene) to form micro-CO3 bridged nickel(II) complexes, [{Ni(mcN3)}2(mu-CO3)](PF6)2 (1a) with a symmetric core in which both nickel atoms are five-coordinate and [Ni(mcN3)(mu-CO3)Ni(mcN3)(MeCN)](PF6)2 (1b) with an asymmetric dinuclear core containing five- and six-coordinate nickel atoms. The magnetic behaviour indicates the existence of antiferromagnetic coupling between the metallic centres. A substantial increase in the value of J occurs when the symmetric five-coordinate nickel species transforms to an asymmetric five- and six-coordinate species by axial coordination of acetonitrile.

Pd(II) and Pt(II) complexes with the anions of the model nucleobases 1-methylthymine (1-MethyH), 1-methyluracil (1-MeuraH), and 1-methylcytosine (1-MecytH) of the types [Pd(dmba)(mu-L)]2 [dmba = N,C-chelating 2-((dimethylamino)methyl)phenyl; L = 1-Methy, 1-Meura or 1-Mecyt] and [M(dmba)(L)(L')] [L = 1-Methy or 1-Meura; L' = PPh(3) (M = Pd or Pt), DMSO (M = Pt)] have been obtained. Palladium complexes of the types [Pd(C6F5)(N-N)(L)] [L = 1-Methy or 1-Meura; N-N = N,N,N',N'-tetramethylethylenediamine (tmeda), 2,2'-bipyridine (bpy), or 4,4'-dimethyl-2,2'-bipyridine (Me2bpy)] and [NBu4][Pd(C6F5)(1-Methy)2(H2O)] have also been prepared. The crystal structures of [Pd(dmba)(mu-1-Methy)]2, [Pd(dmba)(mu-1-Mecyt)]2.2CHCl3, [Pd(dmba)(1-Methy)(PPh3)].3CHCl3, [Pt(dmba)(1-Methy)(PPh3)], [Pd(tmeda)(C6F5)(1-Methy)], and [NBu4][Pd(C6F5)(1-Methy)2(H2O)].H2O have been established by X-ray diffraction. The DNA adduct formation of the new platinum complexes synthesized was followed by circular dichroism and electrophoretic mobility. Atomic force microscopy images of the modifications caused by the platinum complexes on plasmid DNA pBR322 were also obtained. Values of IC50 were also calculated for the new platinum complexes against the tumor cell line HL-60. All the new platinum complexes were more active than cisplatin (up to 20-fold in some cases).