An-Najah Staff

Three diamine-bis(diphenylphosphinobutane)ruthenium(II) complexes, isolated from the
reaction of [Cl2Ru(dppb)] with diamines, have been synthesized and characterized on the basis of
various physico-chemical studies viz., elemental analyses, IR, UV/Vis, FAB-MS, TG-DTA,
EXAFS, EDX and 1H-, 13C- and 31P{1H}NMR spectroscopy. 31P{1H}NMR investigations
confirm that the complex 3 is in cis form while the complexes 1-2 appear in trans form. The
structure of complex 3, cis-[Cl2Ru(dppb)(N-N)] isomer, determined by single crystal X-ray
measurement shows with one solvated dichloromethane and crystallize as monoclinic unit cell
with P2(1)/n space group.

The hemilability of the ether-phosphine ligand [Ph2PCH2CH2OMe] was recorded during complexes 1 and 2 synthesis. The structures of both 1 and 2 have been deduced from elemental analysis, IR, EXAF, FAB-mass spectrometry, 1H, 13C{1H} and 31P{1H} NMR spectroscopy. One of the chloride atoms in 1 was abstracted using AgOTf reagent to prepare the mono-cationic O-Ru-P closed 2. By treatment complex 2 with excess amount of NH4Cl in 2-propanol complex 1 was re-prepared. FAB-MS, EXAF and 31P{1H}-NMR served to monitor the hemilability of the ether-phosphine in 1 and 2 at RT.

Novel Ru(II) complex-based hybrid inorganic-organic materials immobilized via a diamine co-ligand site instead of the conventional diphosphine ligand have been prepared. The complexes were prepared by two different methods: sol-gel and surface modification techniques. The structures of the desired materials were deduced by several available physical measurements like elemental analyses, infrared, FAB-MS and 1H-, 13C- and 31P-NMR spectroscopy. Due to a lack of solubility the structures of xerogel 3 and modified 4 were studied by solid state 13C-, 29Si- and 31P-NMR spectroscopy, infrared spectroscopy and EXAFS. These materials were stable enough to serve as hydrogenation catalysts. Selective hydrogenation of functionalized carbonyls in a,b-unsaturated compounds was successfully carried out under mild conditions in a basic medium using these complexes as catalysts.

An investigation into the potential ruthenium(II) 1-3 complexes of type [RuCl2(P)2(N)2] using triphenylphosphine and 1,3-bis-diphenylphosphinepropane and 3-(triethoxysilyl)propylamine has been carried out at room temperature in dichloromethane under an inert atmosphere. The structural behaviors of the phosphine ligands in the desired complexes during synthesis were monitored by 31P{1H}-NMR. The structure of complexes 1-3 described herein has been deduced from elemental analyses, infrared, FAB-MS and 1H-, 13C- and 31P-NMR spectroscopy. Xerogels X1-X3 were synthesized by simple sol-gel process of complexes 1-3 using tetraethoxysilane as co-condensation agent in methanol/THF/water solution. Due to their lack of solubility, the structures of X1-X3 were determined by solid state 13C-, 29Si- and 31P-NMR spectroscopy, infrared spectroscopy and EXAFS.

Syntheses of four new ruthenium(II) complexes of the [RuCl2(P)2(N)2] type using 2-(diphenylphosphino)ethyl methyl ether (P~O) as ether-phosphine and triphenylphosphine (PPh3) as monodentate phosphine ligands in the presence of [3-(2-aminoethyl)aminopropyl]trimethoxysilane as diamine co-ligand are presented for the first time. The reactions were conducted at room temperature and under an inert atmosphere. Due to the presence of the trimethoxysilane group in the backbone of complexes 1 and 2 they were subjected to an immobilization process using the sol-gel technique in the presence of tetraethoxysilane as cross-linker. The structural behavior of the phosphine ligands in the desired complexes during synthesis were monitored by 31P{1H}-NMR. Desired complexes were deduced from elemental analyses, Infrared, FAB-MS and 1H-, 13C- and 31P-NMR spectroscopy, xerogels X1 and X2 were subjected to solid state, 13C-, 29Si- and 31P-NMR spectroscopy, Infrared and EXAF. These complexes served as hydrogenation catalysts in homogenous and heterogeneous phases, and chemoselective hydrogenation of the carbonyl function group in trans-4-phenyl-3-butene-2-al was successfully carried out under mild basic conditions.

The preparation of new three trans-[RuCl2(dppb)(N–N)] with mixed diamine (N–N) and 1,4-bis-(diphenylphosphino)butane (dppb) ligands, starting from RuCl2(PPh3)3 as precursor is presented. The complexes are characterized on the basis of elemental analysis, IR, 1H, 13C and 31P{1H}NMR, FAB-MS, TG/DTA and single crystal X-ray diffraction studies. Complex (2L1) crystallizes in the monoclinic unit cells with the space group P21. The catalysts are evaluated for their Cinnamic aldehyde hydrogenation. The catalysts show excellent activity and selectivity for the unsaturated carbonyl compound under mild conditions.

In the title compound, [RuCl2(C6H14N2)(C28H28P2)].CH2Cl2, the RuII ion is coordinated in a slightly distorted octahedral environment, formed by two cis-oriented chloride ligands, two cis P atoms of a 1,4-bis(diphenylphosphanyl)butane ligand and two cis-chelating N atoms of a bidentate cyclohexane-1,2-diamine ligand. In the crystal, pairs of molecules form inversion dimers via N-H Cl hydrogen bonds. In addition, intramolecular N-H Cl and weak C-H Cl, C-H N, N-H and C-H hydrogen bonds are observed. One of the Cl atoms of the solvent molecule is disordered over two sites with refined occupancies of 0.62 (1) and 0.38 (1).

Neutral complex 1 and mono-cationic complex 2 were made available using Ph2PCH2CH2OCH3 and 1,2-diphenyl-1,2-ethanediamine ligands. One of the chloride atoms in complex 1 was abstracted by AgOTf to prepare the mono-cationic O–Ru–P closed complex 2. The hemilability of hybrid ether-phosphine ligand in such complexes was monitored by 31P{1H} NMR and confirmed by X-ray single crystal. XRD structure of complex 2 was found to be a Trigonal crystal system with P3 space group and Z = 6.