Synthesis and Reactivity of Ru(II)/Chloro/Hydrido/Carbonyls with Cis Bulky Phosphines:  An Unsaturated Ru(II) Monohydride

Abstract

[RuCl2(CO)2(d t bpe)], d t bpe = tBu2PCH2CH2PtBu2 is synthesized as a mixture of two isomers and is converted to [RuHCl(CO)2(d t bpe)], then [Ru(H)2(CO)2(d t bpe)]. The chloride trans to hydride in [RuHCl(CO)2(d t bpe)] can be replaced by BF4 - or PF6 -, and reaction with NaB(3,5-(CF3)2C6H3)4 gives authentic, five-coordinate [RuH(CO)2(d t bpe)]+, characterized structurally by X-ray diffraction, which reveals the lack of agostic interactions. [Ru(H)2(CO)2(d t bpe)] reacts under mild conditions with CO to give [Ru(CO)3(d t bpe)], with ethylene to give C2H6 and [Ru(C2H4)(CO)2(d t bpe)], and with D2 to give some [Ru(H)(D)(CO)2(d t bpe)]. These results are interpreted in terms of relatively facile dissociation of one end of d t bpe from the metal.

Mononuclear and dinuclear complexes with a [Ru(tBu2PCH2CH2PtBu2)(CO)] core

“…25 The hydride complex 12 showed a characteristic triplet (d −7.97) and singlet (d 110.7) in the 1 H and 31 P{ 1 H} NMR spectra respectively. 5 As expected, there was no evidence for bound triflate ( 19 F NMR). The molecular geometry of 12 was established unequivocally by X-ray crystallography.…”

“…The dichloride complex, [Ru(d t bpe)(CO) 2 Cl 2 ] (2), has been reported by Caulton and co-workers to be formed as part of an inseparable mixture containing all-cis and trans-(CO) 2isomers upon refluxing [Ru(CO) 2 Cl 2 ] 2 with d t bpe under a slow flow of CO. 5 Assignment of all stereochemistries was based upon 31 P/ 13 C NMR spectroscopy and IR data. During one of our first efforts to prepare this mixture, we were able to crystallise the more unusual trans-dicarbonyl isomer (unusual on the grounds of the two p-acceptor ligands occupying trans positions) 6 and confirm the geometry unambiguously through X-ray crystallography, as shown in Fig.…”

“…While examples of ruthenium complexes bearing chelating alkylphosphines are still relatively small in number, 4 of most relevance to our current work were previous studies by Caulton and co-workers who isolated [Ru(d t bpe)(CO) 2 Cl 2 ] (2). 5 However, in contrast to [Ru(dppe)(CO) 2 Cl 2 ], which afforded 1a-d upon silver salt metathesis in the presence of water, the 18-electron d t bpe dichloride (2) first needs to be 'activated' by CO loss to form the isolable coordinatively unsaturated species [Ru(d t bpe)(CO)Cl 2 ] (4). Herein, we report the synthesis and characterisation of a range of complexes including 4 and 8, and their reactions with donor solvents.…”

Synthesis, characterization, reactivity and theoretical studies of ruthenium carbonyl complexes containing ortho-substituted triphenyl phosphanes

“…Elemental analysis of the solid and 31 P NMR confirmed that the product was [Ru(l-Cl)Cl(CO) 2 -(detp)] 2 . Although halide-bridged dimers containing small phosphines have been previously reported [38,[50][51][52][53] examples of ruthenium carbonyl halidebridged dimers containing bulky phosphanes are less common [54][55][56].…”

Preparation of hydride complexes of ruthenium with bidentate phosphite ligands

“…The use of boiling methanol, instead of 2-methoxyethanol, as a solvent yielded the alltrans isomer instead of the cis-cis-trans one [37]. The thermodynamically less stable all-trans isomer 6, due to the mutual competition of both CO ligands for the electronic charge of the metal [38], can therefore be obtained using methanol as solvent.…”