Indenyl ruthenium complex

We reported the use of an indenyl ruthenium complex 2 as a racemization catalyst which did not produce ketones as the byproducts [17]. The metal catalyst requires a weak base like triethylamine and molecular oxygen to be activated. The DKR with 2 in combination with an immobilized PCL was carried out at a lower temperature (60°C) to afford good yields and high optical purities (Scheme 1.15). It is noteworthy that 2 does not require ketone as hydrogen mediator for racemization. 

In 1999, Park s group showed that the indenyl ruthenium complex, depicted in Scheme 4.5, could be applied to the DKR of 1-phenylethanol with Pseudomonas cepacia lipase (PCL) in the presence of molecular oxygen and TEA, without the presence of hydrogen mediators. Both excellent yield and enan-tioselectivity were obtained by using p-chlorophenyl acetate as the acyl donor, as shown in Scheme 4.5. 

The iron species [Fe(X)2 CN(PP)CH(Me) = CH(Me)N(Pr ) ] (X = Cl, Br), containing highly donating imidazolyidene ligands, have been found to be extremely active and efficient catalysts for the atom transfer radical polymerisation of styrene and methylmethacrylate. A variety of indenyl ruthenium complexes containing either phenylacetylide (C = CPh) or vinyl (CH = CHPh) ligands have been found to catalyse the dimerisation of phenylacetylene to ( )-and (Z)-l,4-diphenyl-l-en-3-yne with the activity of the catalyst dependent upon the nature of the phosphine co-ligand bound to ruthenium. The vinylidene-ruthenium(II) complexes [Ru(Cl)(L)2(C = CHR)] (R = Bu, ferrocenyl L =... 

Fig. 6 Indenyl-ruthenium(II) complexes containing chiral allenylidene chains...

Moreover, taking advantage of the regioselectivity shown by the indenyl-ruthenium(II) complexes [Ru(77 -C9H7)(=C=C=CR R )(PPh3)2][PF6], an efficient... 

Fig. 17 Indenyl-ruthenium(II) tr-alkynyl complexes generated from allenylidenes...

Otherwise, the reactions of indenyl-ruthenium(II) allenylidenes [RuCty -CgHy) =C=C=C(R )Ph (PPh3)2][PF6] (R = H, Ph) with ynamines R C CNEtj (R = Me, SiMea) have been reported to yield the alkenyl(amino)allenylidene complexes 41 via insertion of the ynamine into the Cp=Cy allenylidene bond (Scheme 10) [52, 53], This insertion process involves an initial nucleophilic addition of the ynamine at Cy atom of the cumulene, which leads to the cationic alkynyl intermediate complexes 39. Further ring closing, involving the Cp atom, generates the [2+2]... 

Half-sandwich ruthenium complexes bearing a cyclopentadienyl (Cp), a pentamethylcyclopentadienyl (Cp ),or an indenyl ligand. 

Among a series of the 18-electron half-metallocene-type ruthenium complexes (Ru-4, Ru-5, and Ru-6), the indenyl derivative Ru-5 led to the fastest living radical polymerization of MMA.60 In this case, additives such as aluminum alkoxides are not necessary for controlled polymerization. However, addition of an amine such as n-Bu2NH dramatically increased the rate to complete the polymerization in 5 h at 100 °C without broadening the MWDs.61... 

T-acetylide ruthenium complexes with the [Ru (ri -C5R5)L2] fragment (C5R5 = cyclopentadienyl, indenyl L2 = mono- or bisphosphines) as the electron donor group. These complexes display in the visible intense MLCT absorptions, which dominate the (3 responses, and, compared with... 

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