Sodium, cyclopentadienyl-, compound with

NaPsWwOiiii], tetradecaammonium, hentricontahydrate, 27 115 Sodium, cyclopentadienyl-, compound with l,2-dimethoxyethane(l l), 26 341 Sodium henicosaphosphide. (Na.,P.[Pg.368]

Sodium cyclopentadienyl reacts with indium trichloride in ether, tetrahydrofuran, or dioxan, forming the volatile compound InCsHs, which may be obtained as pale yellow needles by sublimation (56). This substance does not melt sharply, but slowly decomposes and darkens at 110°. It is very sensitive to oxidation and is slightly soluble in benzene, in which decomposition takes place it is, however, rather less soluble in ether and petroleiun ether. Water has no action on the compound, but on addition of a little sulfuric acid it is vigorously decomposed. The crystals are slightly sensitive to light. In the preparation of InCsHs an intermediate product, InlCsHsls, can be isolated in very small yield as golden crystals. On sublimation at above 160° it decomposes to form the monocyclopentadienyl compound. 

In 2001, Takahashi and his co-workers developed the first asymmetric ruthenium-catalyzed allylic alkylation of allylic carbonates with sodium malonates which gave the corresponding alkylated compounds with an excellent enantioselectivity (Equation (Sy)). Use of planar-chiral cyclopentadienylruthenium complexes 143 with an anchor phosphine moiety is essential to promote this asymmetric allylic alkylation efficiently. The substituents at the 4-position of the cyclopentadienyl ring play a crucial role in controlling the stereochemistry. A kinetic resolution of racemic allylic carbonates has been achieved in the same reaction system (up to 99% ee). ... 

The earliest work with cyclopentadienyl was reported independently by Kaesz and by Fischer. They carried out reactions using TcCU and sodium cyclopentadienyl in the presence of BELi as a reducing agent. The species Tc(Cp)2H and [Tc(Cp)2H2]+ have been prepared. These compounds are believed to have bent metallocene (see Bent Metallocenes) stractures. The reaction of TcCLi and potassium cyclopentadienyl in THF gives the diamagnetic air-stable Tc(Cp)2Cl, whose stracture is shown in Figure 4. 

The anion Mo(CO)3C5H5 has been prepared by the reaction of the cyclopentadienyl anion with molybdenum hexacarbonyF- and by the reaction of dicyclopentadiene mth molybdenum hexacarbonyl to form [CoH5Mo(CO)3]2, followed by reduction of the latter compound with sodium amalgam. In view of the simplicity of preparing cyclopentadienylpotassium (by deprotonation of cyclopentadiene with potassium hydroxide), the former method is preferable, and is described below. The Mo(CO)3C6H5 anion may be converted to the hydride HMo-... 

The THF in UCI2H2BPZ2THF could easily be replaced by pyridine, giving a dark blue compound. Treatment of a solution of the THF complex in toluene with sodium cyclopentadienyl gave a red-brown solution whose UV/vis spectrum was different from that of the U(III)cyclopentadienyl THF adduct though Still characteristic of a U(III) compound. The same reaction in THF solution, however, did yield a U/f sHslsTHF solution 290). 

Chromium forms a cyclopentadienyl compound similar to ferrocene (p. 499). Cyclopentadienyl sodium reacts with anhydrous chromium (I I) chloride in tetrahydrofuran to give red (C5H5)2Cr. By oxidising this, compounds containing the (C5H5)2Cr+ ion are easily obtained (Cotton and Wilkinson, 1954). When cyclopentadiene mixed with molybdenum or tungsten carbonyl is passed through a tube heated to 300 the dicyclopentadienyl hexacarbonyl is formed (Wilkinson, 1954) ... 

Cyclopentadienyl complexes, as previously discussed, are exceptionally numerous and have been the subject of extensive study. Several routes are available for introducing this ligand into a metal complex. One approach is to react a metal compound with the cyclopentadienide ion, C5H5. This ion can be purchased as the sodium salt in solution it can also be prepared by the following two-step process. 

Solutions of complex compound cyclopentadienyl-dititana in hexane and sodium cyclopentadienyl complex have high catalytic activity. Films with a metallic luster can be obtained by slowly removing the solvent from the formed gel polyacetylene in vacuum. It is assumed that the active complex has a tetrahedral structure. Polymerization mechanism is similar to the mechanism of olefin polymerization on catalyst Ziegler-Natta. Obtained at -80°C cis-polyacetylene films after doping had a conductivity of 240 (Ohm-cm" ). 

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