Lutetium complexes

The unsymmetrical complexes LnPcPc can also be prepared in a stepwise manner (Scheme 8.1, D, upper part) [87, 112-114]. Treatment of phthalonitrile with excess of Lu(OAc)3- H2Oand DBU gives the half-sandwich compound LuPc(0Ac)(H20)2. The latter complex reacts with Na2Nc in 1-chloronaphthalene leading to the formation of LuPcNc [87]. Similarly, the template reaction of unsubstituted and crown-substituted phthalonitriles with lutetium acetate was carried out in boding w-hexanol in the presence of DBU [115-117]. Bi- and tri-nuclear [118] lutetium complexes could also be obtained following this approach [111, 119]. 

The lutetium complex 57 is currently under clinical evaluation as a photosensitizer for the treatment of cancer. This complex possesses a strong broad absorption band centered at 732 nm (247). Upon absorption of light, 57 becomes activated to a long-lived triplet state and reacts with 302 to generate cytotoxic. Complex 57 is also on clinical trial as a photosensitizer for the treatment of atherosclerisis, a vascular disease caused by deposition of cholesterol and other fatty materials in the walls of blood vessels. 

The corresponding yttrium complex is found to be isostructural with the lutetium complex. 

The heterogeneous nature of the reaction makes it a difficult one to study, but it has beer modeled homogeneously with a lutetium complex which undergoes oligomerization Iyj... 

Okuda et al. have investigated a series of yttrium, scandium and lutetium complexes with l,oo-dithiaalkanediyl-bridged bisphenolato (OSSO) ligands a... 

Monocationic Schiff base complexes of gadolinium and lutetium were obtained by employing a highly aminofunctionalized Schiff base ligand as shown in Eq. (15) [170], An X-ray structure analysis of the lutetium complex revealed discrete cations and a distorted square antiprismatic coordination polyhedron. 

The complex has a tetrahedral configuration with Lu-C bonds of 2.42-2.50 A bond length. The bulky 2,6-dimethylphenyl group provides steric limitations in the complex. Ytterbium complex isomorphous with lutetium is also known. The electronic structure and the nature of chemical bonding of the lutetium complex was studied by the INDO method [26]. The MO s of Lu(CgH9)4 ion and the charge distribution are shown in Figs 5.4 and 5.5, respectively. 

The lutetium complex [253] has a structure characterized by a tetrahedral metal core of Lu atoms bound by bridging hydrogens, and tri-A H4 and tetradentate (AIH4 Et20) groups. 

New and more effective polymerization catalysts such as the lutetium complex (C5H5)2LuCH3 is the fastest soluble ethylene polymerization catalyst for producing high density polyethylene. 

The product isolated from the reaction of a 1 1 stoichiometric amount of CO with the lutetium complex was characterized as a monoinsertion product, an acyl. From spectroscopic data, a dihaptoacyl structure involving significant Lu-0 interaction was postulated. With excess CO, a dimeric complex was isolated in which four CO molecules were coupled via one C=C double bond and two C—C single bonds to form an enedionediolate moiety. The condensation of these four CO molecules can be rationalized based on the carbenoid character of the dihaptoacyl carbon atom. This multiple coupling of CO has precedent in early transition metal... 

The lutetium complex can also be obtained by hydrogenolysis in the presence of lithium reagents starting from (CsHs)2Lu(r-C4H9)(thf). The origio of the UH incorporated into this trimer was more difficult to explain than the origin of LiCl in Eq. (17). Perhaps related to this is the fact that the yield in Eq. (18) was 12%. 

The first monomeric porphyrinato rare earth complex was reported in 1974 [49]. However, only a few reports on these systems have appeared in the literature since then. In 1991, Schaverien and Orpent reported the synthesis of the monomeric porphyrinato lutetium complex Lu(OEP)[CH(Si(CH3)2] from the reaction between Lu CH[Si(CH3)3]2 3 and H2OEP in toluene [50]. Eigure 4.33 displays its molecular structure. The complex belongs to the monoclinic system and crystallizes in a space group P2 lc with a = 1.4879(6) nm, 7 = 2.0644(10) nm, c= 1.4161(5) nm, P= 96.38(3)°, V = 4.323(3) nm, andZ = 4. The coordination geometry can be described as square-pyramidal. In the crystal, the porphyrin... 

Carbonylation of the yttrium complex 313 gives the dinuclear enolato complex 314 . The lutetium complex 315 reacts with two molecules of CO to give 316, a process which can be formally viewed as the result of (i) a CO insertion into a Lu—C bond to give an /7 -acyl complex, followed by acyl insertion into a 2,2 -bipyridine C—H bond, and (ii) a second CO insertion followed by SiMes migration . ... 

Towards the end of the second millennium, studies of the transition elements continued to make major contributions to chemical science and technology. The development of new catalysts and reagents represents one area of activity. Examples are provided by the activation of saturated hydrocarbons by rhodium or lutetium complexes, new syntheses of optically active products in reactions which employ chiral metal compounds, and transition metal compounds which catalyse the stereospecific polymerization of alkenes. The ability of transition metal centres to bind to several organic molecules has been exploited in the construction of new two- and three-dimensional molecular architectures (Figure 1.4). New materials containing transition elements are being developed, one... 

As was found in early transition metal and actinide chemistry, the CsMes ligand has allowed the isolation of complexes difficult to obtain by other means. More importantly, however, following the principle of steric oversaturation, the CsMes ligand has provided access to some of the most highly reactive organolanthanide complexes known to date. In addition, as demonstrated by the samarium and lutetium complexes [(C5Mes)2LnH]2,... 

The first structure of a [Ln(phen)2(N03)3] complex was reported in 1992 for the lanthanum compound.It closely resembled the established bipy analogue in that the three nitrate groups were bidentate and the lanthanum was 10-coordinate. The structural information was complemented by a multinuclear solution ( H-, C-, O-, and La) NMR study. The structure of the other extreme member of the series, the lutetium complex, was reported in 1996. Unlike the La complex, but like [Lu(bipy)2(N03)3], the study was not complicated by disorder. The complexes appear to form an isomorpohous and isostructural series. On moving from the lanthanum to the lutetium compound, the Ln—N distances decrease from 2.646(3)-2.701(3) A (La) to 2.462(8)-2.479(8) A (Lu), and the range of Ln—O distances decreases from 2.580(3)-2.611(3) A for the lanthanum compound to 2.364(8)-2.525(6) A for the lutetium complex. Several structures have subsequently been reported of other [Ln(phen)2(N03)3] systems. [Ln(phen)2(N03)3] (Ln = Pr, Lu, Dy, are isostructural the individual complex... 

Benzenemethanamine, iV.iV-dimethyl-. lithium complex, 26 152 lutetium complex, 27 153 palladium complex, 26 212... 

Fluorosulfate, tetrabutylammonium, 26 393 Formic acid, rhenium complex, 26 112 Furan. tetrahydro-, iron complex, 26 232 lanthanide-lithium complexes, 27 169 lutetium complex, 27 152, 153, 161, 162 magnesium complex, 26 147 neodymium complex, 27 158 neodymium and samarium complexes, 26 20... 

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