Ilse Y. Guzman-Jimenez

Synthesis and characterization of platinum(II) complexes with 3-methylpiperidine: crystal and molecular structure of [Pt(3-methylpiperidine)2(malonato)]·H2O

Abstract A series of new platinum complexes of the type [Pt(3-mepip) 2 X] (where 3-mepip=3-methylpiperidine, and X=dichloro, sulfato, oxalato, malonato, methylmalonato, dimethylmalonato, tartronato, 1,1-cyclopropanedicarboxylato (CPDCA) or 1,1-cyclobutanedicarboxylato (CBDCA) ligand) were synthesized and characterized by elemental analysis, IR spectroscopy and 195 Pt nuclear magnetic resonance spectroscopy. The crystal structure of [Pt(3-mepip) 2 (malonato)]·0.79H 2 O was determined by single crystal X-ray diffraction. In this complex platinum has slightly distorted square planar geometry with two adjacent corners being occupied by two nitrogens of 3-methylpiperidine, whereas the remaining two adjacent corners are occupied by two oxygen atoms of the malonato group. An intricate network of intermolecular hydrogen bonds holds the crystal lattice together. In the other complexes, 3-mepip acts as non-leaving ligands, whereas the carboxylato ligands act as leaving groups.

Synthesis and characterization of piperidine platinum(II) complexes with dicarboxylates: crystal and molecular structure of cis-[Pt(piperidine)2Cl2]·H2O

Abstract A series of new platinum complexes of the type cis-[Pt(PIP)2X] (where PIP=piperidine and X=dichloro, sulfato, oxalato, malonato, methylmalonato, dimethylmalonato, tartronato, 1,1-cyclopropyldicarboxylato (CPDCA) or 1,1-cyclobutyldicarboxylato (CBDCA) ligand) were synthesized and characterized by elemental analysis, IR, and 195Pt nuclear magnetic resonance spectroscopy. The crystal structure of cis-[Pt(PIP)2Cl2]·H2O was determined by X-ray crystallography. In this complex platinum has slightly distorted square planar geometry with two adjacent corners being occupied by two nitrogen atoms of piperidine, whereas the remaining two adjacent corners are occupied by two chloride atoms. An intricate network of intermolecular hydrogen bonding holds the crystal lattice together. In these complexes, piperidine acts as non-leaving ligand, whereas the dicarboxylic acids act as leaving groups.

SYNTHESIS, CHARACTERIZATION, AND REPRESENTATIVE CRYSTAL STRUCTURE OF LIPOPHILIC PLATINUMII (HOMOPIPERAZINE)CARBOXYLATE COMPLEXES

Abstract A series of new lipophilic platinum(II) complexes of the type [Pt(HPIP)L2] and [Pt(HPIP)L] (where HPIP = homopiperazine; L = acetate, propionate, butyrate, pentanoate, hexanoate, heptanoate, octanoate, nonanoate, decanoate, undecanoate, laureate, tridecanoate, myristate, pentadecanoate, palmitate, or heptadecanoate; and LL = oxalate, or tartronate) were synthesized and characterized by elemental analysis, IR, 13CNMR, and 195Pt NMR. In addition, the crystal structure of a representative complex [PtII(HPIP)(pentadecanoate)2], was determined by X-ray diffraction. The crystals were monoclinic, space group P21/c, with a = 28.212(6)Å, b = 3.661(3)Å, c = 10.218(2)Å, and Z = 4. A total of 3940 reflections were collected, and the structure refined to R1 = 0.0522 and wR2 = 0.1333. The slightly distorted square plane of the platinum included the amino groups of the HPIP molecule in cis positions and oxygens from two monodentate pentadecanoates. The HPIP molecule was in a boat conformation and formed five- and six-member chelating rings with platinum. Together, these molecules formed an intricate network of intermolecular hydrogen bonds that held the crystal lattices together.

Synthesis, characterization, structural and theoretical analysis of a series of electron deficient, monomeric thallium iron carbonylate isostructural and isolobal to diiron nonacarbonyl

Abstract Extended Huckel and density functional calculations on the isoelectronic [Fe2(CO)6(μ-CO)3−n{μ-TlFe(CO)4}n]n− (n=0–3) series show that the nature of the Fe⋯Fe interaction is quite similar within the series, despite of the different observed internuclear separations. An orbital explanation is provided to explain why these compounds are diamagnetic despite of the absence of a real FeFe bond. In the cases of n=1–3, the formation of dimers allows the release of the electron deficiency on Tl centers through donation from an iron lone pair, leaving almost unchanged bonding within the associated monomers. The stability of the dimers with respect to dissociation appears to be limited by the destabilizing ionic interaction between the negatively charged monomers.

Self-assembly of organometallic clusters onto the surface of gold

We report the preparation and characterization of thin films generated via the solution-phase self-assembly of organometallic chalcogen-containing cluster compounds onto the surface of gold. The following anionic complexes were used as thin film precursors: wFe (CO) Ex and wHFe (CO) Ex , where EsS, Se, and Te. The films were prepared by adsorption from organic 2 yy 39 3 9 solvents (i.e. methanol, acetonitrile, acetone, and dicholoromethane ) onto evaporated gold and were characterized by ellipsometry, polarization-modulation infrared reflection-absorption spectroscopy (PM-IRRAS), X-ray diffraction (XRD), atomic force micros- copy (AFM), quartz crystal microbalance (QCM) and X-ray photoelectron spectroscopy (XPS). The data demonstrate that the clusters strongly attach to gold and that the films most likely exist as bilayers rather than monolayers. 2001 Elsevier Science B.V. All rights reserved.