[RuCp(PR₃)(CH₃CN)₂]PF₆ (R = Ph, Me, Cy). Convenient Precursors for Mixed Ruthenium(II) and Ruthenium(IV) Half-Sandwich Complexes

Abstract

The reaction of [RuCp(CH 3 CN) 3 ]PF 6 (1) with the monodentate ligands PR 3 (R ) Me, Ph, Cy) affords the cationic complexes [RuCp(PR 3 )(CH 3 CN) 2 ]PF 6 (2a-c) in high yields. The CH 3 -CN exchange kinetics has been studied by NMR, suggesting a dissociative mechanism. Due to van der Waals repulsive interactions between PCy 3 and the nitrile ligands, CH 3 CN is particularly labile in 2c. The chemistry of 2a-c has been further investigated with respect to substitution and oxidative addition.

Formation of Ruthenium−Aminocarbene Complexes from Aldimines and Aminals

“…The RuϪN(py) and RuϪCl bond lengths are 2.046(3) and 2.414(1) Å . The RuϪC (15) bond length is 1.915(3) Å , which is similar to that in other heteroatom-stabilized ruthenium carbene complexes (cf. 1.959(1) Å in 9a [1] ).…”

“…In these reactions, the aminal at first obviously transforms back into the starting aldimines and amines. Thus (15) in high yields (Scheme 6). Interestingly, with 2b the reaction does not stop at the aminocarbene stage, but proceeds further to give the olefin complex 16.…”

Scope, mechanism and diene inhibition of isomerization of allylic alcohols to saturated ketones catalyzed by ruthenium(II)-cyclopentadienyl complexes

“…The presence of substitutionally labile acetonitrile ligands [20] makes 1 an ideal starting complex for in situ testing. When 1 is used as catalyst precursor, only low turnover numbers (TONs; 115 after 1 h; see Table 2) are obtained.…”

Adducts of Cyclotriphosphorus Complexes with Cyclopentadienyl Ruthenium Fragments: Synthesis, Solid‐State Structure and Solution Behaviour

“…The 2D 31 P{ 1 H} EXSY spectra were recorded using a modified NOESY sequence with 1 H decoupling during acquisition: 400 increments of size 3 K (with 400 scans each) covering the full range in both dimensions were collected with a relaxation delay of 0.25 s and mixing times of 50, 100 and 500 ms. [42,43] Analytical data for carbon, hydrogen, nitrogen, and phosphorus were obtained from the Microanalytical Laboratory of the Department of Chemistry of the University of Firenze. [19,20,38] The 1 H NMR spectroscopic data of the dinuclear adducts 6-15 and the 31 P{ 1 H} resonances of the phosphane ligands (triphos and PR 3 ) are reported in this section. The uninformative 1 H signals of the aromatic protons of triphos and of the PPh 3 derivatives, occurring in the expected region (7.6-6.9 ppm), are not reported.…”

“…[13,34] The phosphorus atom of the PR 3 ligand yields a doublet due to coupling with P F ; both the chemical shift and the coupling constant of the phosphane ligand are in the range observed for [CpRu(PR 3 )(PR 3 Ј)(L)] complexes. [38] This could indirectly suggest that the donor/acceptor properties of the "naked" phosphorus atoms in the "ligand" [(triphos)M(η 3 -P 3 )] should be similar to those of the phosphanes. Signals due to the P atoms of the cyclo-P 3 unit are split into three distinct multiplets in the high-field region with integral ratios of 1:1:1.…”