Co-ordinatively unsaturated pentamethylcyclopentadienyl ruthenium(II) chloro and methoxy complexes

Abstract

CP*RUOM~)~, (2), (Cp* = qS-C5Me5) has been prepared from ( C ~* R U C I ~) ~, (I), in MeOH and converted to (CP*RUCI)~, (3), in pentane with Me,SiCI; both complexes (2) and (3) readily react to give Cp*RuL2X complexes on addition of the appropriate ligands L.Since the discovery of ( c p * R ~C l ~) ~t in 19841 several groups24 have exploited the synthetic potential of this material for the synthesis of organometallic, in particular Cp*Ru complexes (Cp* = C5Me5). Co-ordinatively unsaturated Ru" species should be able to play a key role since they -t Note udded in proof: recent X-ray structure determinations have disclosed ( I ) and (2) to be dirneric (U. Koelle, R. Boese, N. Klaff, and G. H. Herberich. to be published) and (3) to be a tetrarner in the solid

Synthesis, Structure and Reactivity of Homo‐ and Heterobimetallic Complexes of the General Formula [Cp*Ru(μ‐Cl)3ML] [LM = (arene)Ru, Cp*Rh, Cp*Ir]

“…Aromatic solvents, on the other hand, are not suited because of the very high tendency of the Cp*Ru + fragment to form sandwich complexes of the general formula [Cp*Ru(arene)]-X. [14][15][16]22] When complex 8 was dissolved in benzene, crystals of the ionic complex [Cp*Ru(C 6 H 6 )][Cp*RhCl 3 ] (12) formed after a few hours (Scheme 3). Larger amounts of 12 could be obtained by slow diffusion of hexane into a solution of 8 in benzene.…”

“…[13][14][15][16] The reaction of 4 with two equivalents of the dimeric half-sandwich complex [(π-ligand)MCl 2 ] 2 was thus expected to give the mixed complex [Cp*Ru(µ-Cl) 3 M(π-ligand)] in an entropically favored reaction. Complex 4 can be obtained by reduction of [Cp*RuCl 2 ] 2 with LiHBEt 3 [14] or with Zn.…”

“…[15] Alternatively, it can be obtained by reaction of the methoxy-bridged complex [Cp*Ru(µ-OMe)] 2 (5) with Me 3 SiCl. [16] We chose the latter method for our reactions.…”

Notes on selectivity aspects in sorbic acid and sorbic alcohol hydrogenation

“…[Cp*Ru(sorbic acid)]CF 3 SO 3 preparation Ruthenium active catalyst was prepared by the method described in literature [5,10,11]. The [Cp*RuCl 2 ] n (0.013 g) was dissolved in ether (5 ml) with excess of sorbic acid (0.15 g), zinc powder (0.15 g) and silver triflate (0.02-0.03 g) and stirred at laboratory temperature for 2.5 h. The orange solution of [Cp*Ru(sorbic acid)]-CF 3 SO 3 (0.08 mmol) was obtained.…”

Selective two-phase hydrogenation of sorbic acid using [Cp*Ru(sorbic acid)]+ catalyst

“…The catalyst was prepared by procedure described in literature [5,6]. Further experiments were carried out with catalyst obtained by different preparation [7] methods.…”