Cobalt complexes cyclopentadienyl

Cobalt, cyclopentadienyl complexes with thioformaldehyde, 55, 14 Cocaine analogs, isoxazolines, 60, 297 Coenzyme factor 420, synthesis, 55, 192 Colloidal media, iodination of pyrazoles in. 57, 344... 

Treatment of 5-phenyl-l,3-thiaselenole-2-thione (51) with sodium ethoxide in the presence of the cyclopentadienyl complex [Co(cp)l2CO] in ethanol also results in ring opening with formation of the stable cobalt cyclopentadienyl complex (52) (Equation (6)) <89BCJ3266>. 

The groups of both Stephenson (1442) and Maitlis and co-workers (1443) independently prepared pentamethylcyclopentadienyl complexes [Cp M(S2CN- 2)2] (M = Rh, Ir R =Me, Et) upon addition of 2 equiv of dithiocarbamate salt to [Cp MCl(p-Cl)]2. Like the analogous cobalt cyclopentadienyl complexes, they contain both a monodentate and a bidentate dithiocarbamate [Cp Rh(S2CNMe2)2] (319) (Fig. 180) is characterized by the v(C—N) vibrations spectrum at 1392 and 1530 cm , respectively, in the IR spectrum. In solution, interconversion of the two dithiocarbamates occurs (Fig. 180). The NMR line shape analysis suggests that it occurs via a dissociatively controlled intramolecular mechanism. 

Cycloalkenes, into if-allyl palladium complexes, 8, 363 Cycloalkenyl rings, metal complex conformational interconversions, 1, 414 Cycloalkynes, in nickel complexes, 8, 147 (Cyclobutadiene)cyclopentadienyl complexes, with cobalt, polymercuration, 2, 435 Cyclobutadienes... 

Although mixed carborane-cyclopentadienyl complexes, predominantly those of cobalt, are the metallocarboranes that have received the most... 

There has been significant interest in substituting cobalt for other transition metals giving rise to what are known as Pauson-Khand type reactions.60 In 1996, Buchwald and co-workers showed that a titanium -cyclopentadienyl complex (45) could be used sub-substoichiometrically in the reaction (46->47 - Scheme 18).61,62... 

Many organometallic complexes use cod as a ligand because it can be easily substituted. For that reason, many cobalt cyclooctadiene complexes are important in catalytic reactions, particularly when used with cyclopentadienyl in complexes (Section 5.1.2). ... 

Cyclopentadienyl complexes of cobalt exist mainly in three oxidation states Co Co, and Co. Co is represented by complexes of the type CpCoL2, where L is CO, alkene, alkyne, or phosphine. Apart from derivatives of cobaltocene, half-sandwich complexes (see Half-sandwich Complexes) (CpCoX)2 or CpCoLX with cobalt in oxidation state II are known. CpCo occurs in various CpCoL Xm compositions (Section 9.2). 

The formation and properties of many other complexes are reported in the literature. These include a cyclopentadienyl-titanium(lll) complex with maleic hydrazide (81IC2084), a nickel(ll) and cobalt (II) complex of... 

Phosphanylalkyl)cyclopentadienyl complexes of cobalt, rhodium, and iridium are known. In some cases, not only the synthesis and structure of such complexes have been described, but a number of reactions have also been investigated. 

J. P. Dieks, M. Zubair, E. S. Davies, C. D. Garner, C. Schulzke, C. Wilson and J. MeMaster, Synthesis, Strueture and Redox Properties of Asymmetric (Cyclopentadienyl)(ene-l,2-dithiolate)cobalt(III) Complexes Containing Phenyl, Pyridyl and Pyrazinyl Units, Eur. J. Inorg. Chem., 2015, 3550-3561. 

In addition to the release of carbon monoxide, transition metal carbonyl complexes have also found applications in anticancer chemotherapy [212], radiolabelling [213-216], and as photosensitisers. The cobalt complex shown in Fig. 14 a demonstrates a higher anticancer activity than cis-platin in certain mammary tiunor cells Hnes [217,218]. Complexes such as Tc-99m(I)(CO)3(OH2)3 along with hydroxymethyl phosphine derivatives [219] and the cyclopentadienyl complex shown in Fig. 14b have useful radiopharmaceutical applications, in diagnosis, using Tc, as the metal centre, and in therapy based on Re and Re isotopes [220]. 

The preparation of two cyclo-octatetraene-gold complexes, (ct)AuCl and (cot)-AU2CI4, has been reported. The structures of biscyclo-octatetraenyl complexes of titanium, vanadium, thallium, and uranium, were deduced from their i.r. spectra. Protonation of (p-cyclo-octatetraene) (p-cyclopentadienyl) complexes has been studied. For the ruthenium and osmium complexes protonation occurs on the eight-membered ring to give CgH moiety co-ordinated to the metal atom via both an T -alkyl and an olefin-metal bond. For the cobalt and rhodium complexes a bicyclic cation (287) is produced which undergoes isomerization to the monocyclic (288). ... 

The use of a cyclopentadienyl ligand containing a pendant phosphine arm allowed the isolation of the cobalt alkyne complexes [<5o(ti5 i -C5H4CH2CH2l Bu 2)(Tl -PhCCR)] (R = H, Hi). In the case of ethyne, the alkyne complex could not be isedated and the vinylidene complex [ 50(115 I-C5H4CH2CH2PBu 2)(=C=CH2)1 was observed. 

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