Cobalt dicyclopentadienyl

Chemical reduction of 177 by dicyclopentadienyl cobalt is different from that of a thiophene derivative and leads to the removal of a heteroatom to yield 213. The latter reacts with tellurophene and Fc3(CO)l2 to give 214 [97JCS(D)1579]. 

Dibenzotellurophene, [RhCp Cl2]2, and silver inflate yield the ri (Te) coordinated product 329 [97JCS(D) 1579]. In the absence of silver triflate, species 330 is formed. Reduction of 329 with dicyclopentadienyl cobalt results in 331. If, however, this process is conducted in the presence of Fe3(CO)i2, ring-opened products 332 and 333 are isolated. 

Interaction of dicyclopentadienyl cobalt and carbon monoxide at 90-150° and atm yields the red-brown compound C5H5Co(CO)2 as a readily volatile liquid (mp —22°, bp 139-140°/710 mm with partial decomposition) which is decomposed in air but forms stable solutions in organic solvents if air is excluded. With water neither solution nor rapid hydrolysis is observed 60, 61, 159). 

Diiodomethane added dropwise at 20° to dicyclopentadienyl cobalt in benzene, stirred 4 hrs., Altered, coned, in vacuo by warming briefly at 30°, the residue containing the intermediate dissolved in methanol, and stirred 0.5 hr. at 35° cyclopentadienyl cyclohexadienyl cobalt iodide. Y 94%. G. H. Herberich and J. Sdiwarzer, B. 103, 2016 (1970). 

Diindenyl cobalt, Co (09117)2, may be produced by the interaction of indenyl potassium and the ammine [Co (NH ) 4] (SON) 2 in liquid ammonia (87). It forms black lustrous crystals which can be sublimed without decomposition they slowly sinter at 160° and melt rather gradually at about 180°. The compound is very soluble in benzene, ether, and alcohol but less soluble in petroleum ether, forming brown solutions. It is considerably less sensitive to oxidation than the dicyclopentadienyl, Co (05115)2, but powerful oxidizing agents convert it into the yellow [00(09117)2]+ ion (87), which may also be obtained by a Grignard reaction (151). 

These were made on the uncharged dicyclopentadienyls of vanadium, chromium, iron, cobalt, nickel, ruthenium, manganese, and magnesium,... 

Zirconium Neodecanoate Cobalt Pentanedione Ferric Pentanedione Ferrous Dicyclopentadienyl Ferrous Pentanedione Titanium Pentanedione Cobalt Dicyclopentadienyl Vanadium Neodecanoate Ferrous Stearate Ferric Naphthenate Control... 

Synthesis of ferrocene in high yield by this method has been reported by a number of investigators (18,34-36,38). Wilkinson et al. (36) have described the preparation of ferrocene, and dicyclopentadienyl compounds of cobalt and nickel in yields of 80-90% anhydrous diethylamine served both as solvent and acceptor for hydrogen halide. This procedure for preparing ferrocene has been published in detail in Organic Synthesis (18). 

Many 7i-cyclopentadienyl complexes may be prepared from the reaction of alkali metal cyclopentadienides with ammonia-soluble transition metal salts such as nitrates and thiocyanates in liquid ammonia (2-30). The amine complexes, [M(NH3) ] (C5H5)2, lose ammonia when heated in vacuo, and the uncharged dicyclopentadienyl complexes of iron, cobalt, nickel, chromium, and manganese are obtained. 

Simultaneously a proton is transferred from the carbon atom of alcohol to the solvent. Other mechanisms of oxidative processes in the presence of metal complexes are also presented in the literature. For example, the Co, Mn, and Pt complexes complexes oxidize olefins presumably by the one-electron mechanism. The reaction of O2 with cobalt dicyclopentadienyl derivatives is accompanied by the oxidation of a-diketones and o-quinones. 

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