Synthesis and Reactivity of Tethered η¹:η⁶-(Phosphinoarene)ruthenium Dichlorides

Abstract

The coordination properties of ortho- and meta-substituted [(2-diphenylphosphanylethyl)phenyl]methanol 4a and 4b toward ruthenium(II) have been investigated. To ensure coordination of both the arene and the tethered phosphine, the labile ruthenium arene dimer [RuCl2(EtO2CC6H5)]2 (7) was synthesized and structurally characterized. Both the ortho and meta isomers [Ru(4a)Cl2] (9a) and [Ru(4b)Cl2] (9b) were characterized by X-ray crystallography. The lack of reactivity of the benzylic alcohol functionality in complexes 9a and 9b toward various P and C electrophiles is rationalized with extended Hückel calculations.

Dinuclear (Arene)ruthenium Complexes Containing a Chiral‐at‐Phosphorus Phosphanido Bridge

“…An optically active mixture (de = 4 %) of phosphanido-bridged complexes [(η 6 -C 6 Me 6 )Ru 2 {µ 2 -(R)-PPh(CH 2 ) 2 CHMe-η 6 -Ph}(µ 2 -Br) 2 ] + (6), containing the (R C ,S P ) and (R C ,R P ) diastereomers, is obtained upon heating of 4 in bromobenzene. The molecular structure of [6][BF 4 ] reveals that the two diastereomers (R C ,S P )-6 and (R C ,R P )-6 exist as two conformers.…”

“…The complete loss of the arene ligand can be an undesired side-reaction during a catalytic process, although the stability of the (arene)ruthenium moiety can be increased by arene ligands containing chelating substituents. [5] The synthesis of such (arene)ruthenium complexes can be achieved by intramolecular arene ligand exchange at the ruthenium atom, which works only if either an electronpoor arene ligand is replaced by an electron-rich one [6] or if the reaction can take advantage of the chelate effect.…”

Preparation, Reactivity and Peptide Labelling Properties of (η6‐Arene)ruthenium(II) Complexes with Pendant Carboxylate Groups

“…Coupling reactions by the carbodiimide method with EDC afford water-stable complexes of the type [(η 6 -C 6 Me 6 )Ru{η 6 -C 6 H 5 (CH 2 ) 3 C(O)R}](OTf) 2 [R = trpOMe (11), pheOMe (12), glyglyOEt (13) nylalanine residues but also for the more general N-terminal labelling of peptides. Furthermore, the recent report that [{η 5 -C 5 H 4 (CH 2 ) 2 NH 2 -κN}Ru(CH 3 CN) 2 ](PF 6 ) with its tethered amine side-chain can quantitatively label the phenylalanine side-chain of the hormone secretin [19] suggests that a hemilabile carboxylate coordination might also enhance the π-complexing ability of (η 6 -arene)ruthenium() complexes in aqueous solution. We have, therefore, prepared compounds of the type [{[η 6 -C 6 H 5 -(CH 2 ) n COOH]Ru(µ-Cl)Cl} 2 ] (n ϭ 1, 3) and studied their reactivity and peptide labelling properties.…”

Combinatorial Catalysis with Bimetallic Complexes: Robust and Efficient Catalysts for Atom‐Transfer Radical Additions

“…The complexes [(dppb)ClRu(m-Cl) 2 (m-OH 2 )RuCl(dppb)], [21] [(dcypb)(N 2 )Ru(m-Cl) 3 RuCl(dcypb)], [22] [Cp*Rh(m-Cl) 3 RuCl-(PPh 3 ) 2 ], [11] [{(C 6 H 5 CO 2 Et)RuCl(m-Cl)} 2 ], [23] [{(cymene)RuCl-(m-Cl)} 2 ], [24] [{(C 6 H 6 )RuCl(m-Cl)} 2 ], [25] [{(C 6 Me 6 )RuCl(m-Cl)} 2 ], [24] [{(1,3,5-C 6 H 3 Et 3 )RuCl(m-Cl)} 2 ], [26] [{(1,3,5-C 6 H 3 iPr 3 )RuCl(m-Cl)} 2 ], [26] [{(h 3 :h 3 -C 10 H 16 )RuCl(m-Cl)} 2 ], [27] [{Cp*RuCl(m-Cl)} 2 ], [28] [{Cp*RhCl-(m-Cl)} 2 ], [29] [{Cp*IrCl(m-Cl)} 2 ], [{(ppy) 2 Rh(m-Cl)} 2 ] (ppy = pyridin-2-yl-2-phenyl), [30] [{(allyl) 2 Rh(m-Cl)} 2 ] (allyl = h 3 -C 3 H 5 ), [31] [{(cod)Rh-(m-Cl)} 2 ] (cod = h 4 -cycloocta-1,5-diene), [32] [{(CO) 2 Rh(m-Cl)} 2 ], [33] [{(tpc)Rh(m-Cl)} 2 ] (tpc = h 4 -tetraphenylcyclopentadienone), [34] [{(cod)Ir(m-Cl)} 2 ], [35] [{(PEt 3 )PdCl(m-Cl)} 2 ], [36] [{(C 9 H 12 )Pd(m-Cl)} 2 ] (C 9 H 12 = ortho-metalated N,N'-dimethylbenzylamine), [37] [{(PEt 3 ) 2 Pt-(m-Cl)} 2 ](BF 4 ) 2 , [38] and [{(PEt 3 ) 2 Pd(m-Cl)} 2 ](BF 4 ) 2 [38] were prepared according to literature procedures. The complex [{(allyl)Pd(m-Cl)} 2 ] was purchased from Fluka.…”