Preparation and reactivity of 16-electron ‘half-sandwich’ ruthenium complexes; X-ray crystal structure of (η⁵-C₅Me₅)Ru(PPrⁱ₃)Cl

Abstract

The new 16-electron ruthenium compounds (v5-C5Me5)Ru(L)CI [(l), L = PPri,; (2), L = PCy3) (Cy = cyclohexyl) were prepared from [ ( ~p -C ~M e ~) R u C l l ~ and PPri3 or PCy3, respectively, and the X-ray crystal structure of (1) has been determined; reactions of the title compounds with CO, C2H4, pyridine, and PhSiH3 are described.A plethora of mechanistic and synthetic information has been reported regarding compounds of the type (qS-CSHS)FeL2X, and related Ru and 0 s systems. 1 In many instances reactive 16-electron intermediates formed via thermal or photoinduced dissociation of L play an important role in the chemistry of these species.2 Here we report the preparation, characterization, and initial reactivity studies of stable, co-ordinatively unsaturated 'half sandwich' compounds (qs-CsMeS) Ru( PR3)Cl.Combination of methylene chloride solutions of PR3 [4 equiv.; R = Pri or Cy, (Cy = cyclohexyl)] and [(qs-CSMeS)-RuC1I43 (1 equiv.) at room temperature produced an immediate colour change from dark orange to deep blue. The highly crystalline 16-electron complexes (q~-CSMeS)Ru(L)C1 [(1), L = PPri,; (2), L = PCy3] were isolated as blue crystals from pentane in 92 and 82% yields, respectively (equation 1).Both reactions are quantitative in [zH,]benzene by IH n.m.r. spectroscopy. Compounds (1) and (2) were charac-and R u C ~] ~.

Synthesis and Chemistry of the 16-Electron Osmium Complex [OsBr(η5-C5Me5)(PiPr3)]

“…It is noteworthy that samples of 2 obtained by recrystallization under N 2 had a completely different morphology to those crystallized under argon. [1] and is consistent with the more basic nature of the osmium center. Coordination of CO to the osmium center destroys the effective C s symmetry of 2, as indicated by NMR spectroscopy.…”

“…[1] These complexes, prepared by addition of the appropriate phosphane in one step from the tetrameric ruthenium species [RuClCp*] 4 , [2] have proven to be valuable starting materials for the synthesis of various silyl, [3] silene, [4] and metallacyclic [5] complexes. Analogous 16-electron complexes of osmium are also expected to be useful synthons, but they have yet to be reported.…”

Structure and Reactivity of Coordinatively Unsaturated Half‐Sandwich Iron, Ruthenium and Osmium Complexes

“…In 1988, Tilley and co-workers prepared the compounds [Cp*RuCl(PR 3 )] (R ϭ iPr, Cy) by reaction of tetrameric, cubane-like [(Cp*RuCl) 4 ] [24] with one equivalent of the corresponding phosphane in dichloromethane. [25] Almost simultaneously, Chaudret and co-workers also reported the synthesis of these compounds by reduction of the Ru III precursors [Cp*RuCl 2 (PR 3 )] (R ϭ iPr, Cy, tBu), usually generated in situ by reaction of [Cp* RuCl 2 ] n with the appropriate amounts of phosphane and Zn in a variety of solvents. [26] The complexes [Cp*RuCl(PMetBu 2 )], [27] [Cp*RuCl(PPhiPr 2 )], [28] [Cp*RuCl(PMeiPr 2 )], [29] and [Cp*RuCl(η 1 -(P)-PCy 2 CH 2 CH 2 OMe)] (bearing a pendant ether group) [30] have also been synthesized by following any of the methods outlined above.…”

“…These compounds display ''folded'' structures in the solid state and have been prepared by reaction of [(Cp*RuCl) 4 ] [24] [25] represented in Figure 3. Table 1.…”

Notizen: Chirale Ruthenium-Halbsandwichkomplexe des Schwefelmonoxids und Schwefeldioxids [1] / Chiral Ruthenium Halfsandwich Complexes of Sulfur Monoxide and Sulfur Dioxide [1]

“…(1) ist die Verfügbarkeit elektronen reicher und sterisch abgeschirm ter koordinativ unge sättigter Teilchen ML". Die kürzlich isolierten 16-Elektronen-K om plexe [C5M e5R uC l(PR 3)] (R = Iso propyl (1), Cyclohexyl (2)) [6] entsprechen diesen Forderungen in idealer Weise. Tatsächlich lassen sich 1 und 2 mit Thiiran-l-oxid glatt zu den neuen SO-Komplexen 3 und 4 umsetzen (Gl.…”