Half sandwich platinum group metal complexes containing tetradentate N-donor ligand bearing two pyrazolyl-pyridine units linked by an aromatic spacer

Abstract

a b s t r a c tReaction of the bis-bidentate ligand, 1,3-bis((3-(pyridin-2-yl)-1H-pyrazol-1-yl)methyl)benzene (NN\NN), containing two chelating pyrazolyl-pyridine units connected by an aromatic spacer with platinum group metal complexes results in a series of cationic binuclear complexes, [(g 6 -arene) 2 Ru 2 (NN\NN)Cl 2 ] 2+ (arene = C 6 H 6 , 1; p-i PrC 6 H 4 Me, 2; C 6 Me 6 , 3), [(g 5 -C 5 Me 5 ) 2 M 2 (NN\NN)Cl 2 ] 2+ (M = Rh, 4; Ir, 5), [(g 5 -C 5 H 5 ) 2 M 2 (NN\NN)(PPh 3 ) 2 ] 2+ (M = Ru, 6; Os, 7), [(g 5 -C 5 Me 5 ) 2 Ru 2 (NN\NN)(PPh 3 ) 2 ] 2+ (8) and [(g 5 -C 9 H 7 ) 2 Ru 2 (NN\NN)(PPh 3 ) 2 ] 2+ (9). All these complexes have been isolated as their hexafluorophosphate salts and fully characterized by use of a combination of NMR spectroscopy, IR spectroscopy and mass spectrometry. The solid state structures of three complexes, [2][PF 6 ] 2 , [4][PF 6 ] 2 and [6][PF 6 ] 2 , has been determined by X-ray crystallographic studies.

Study of new mononuclear platinum group metal complexes containing η5 and η6 – Carbocyclic ligands and nitrogen based derivatives and formation of helices due to NH⋯Cl interactions

“…These bond distances are comparable to those in the related complex cations reported earlier from our laboratory [28][29][30][31][32][33][34][35]. The NARu bond distances in these complexes are centered at around 2.089 (2) Å and are in good agreement with similar type of complexes reported earlier [28][29][30][31][32][33][34][35]. The RuACl bond distance in complexes 2 and 4 are 2.3776(7) and 2.3955(7) Å whereas in complex 15 the Ru-P distance is 2.3306(6) Å.…”

“…In addition, the four-coordinated, pseudo-tetrahedral geometry makes them particularly suitable for investigation of the stereochemistry of reactions at the metal center [27]. In recent years we have been carrying out reactions of g 5 -and g 6 -cyclic G-perimeter hydrocarbons metal complexes with a variety of nitrogen-based ligands [28][29][30][31][32][33][34][35] including various poly-pyridyl ligands. Ruthenium compounds of these types of nitrogen-based ligands have a capacity to function as catalysts for the oxidation of water to dioxygen [36,37].…”

η 5 and η 6 - cyclic π-perimeter hydrocarbon platinum group metal complexes of 3-(2-pyridyl)pyrazole derived ligands with a pendant nitrile group: Syntheses, spectral and structural studies

“…The selected bond angles given in the tables are also within the range of reported literatures. 11,26 The N-Ru-N angles have values of 75.28 (19), 75.57 (13) and 74.9(2) • deviated from 90 • as per demand of the bite of the ligand which is in accordance with the literature value of the platinum group pyridyl pyrazole complexes. 26…”

“…These ligands * For correspondence react with Ag(I) salts to give a range of infinite coordination networks or dimeric 'boxes' in which the pyrazolyl-pyridine chelates and the aromatic nitrile groups both participate in coordination to Ag(I) ions. 3 Although there have been some reports of the complexes of η 6 and η 5 -platinum group metal complexes with pyridylpyrazole derived ligands, 10,11 complexes derived from 3-(2-pyridyl)pyrazole with a pendant nitrile group have not yet been explored. The nitrile group being an electronrich centre, it has the possibility to bind with a metal ion through the nitrogen atom.…”