Cyclopentadienyl cesium

This reaction has been used to make crystalline triphenylmethyl derivatives that have been characterized by X-ray structure determinations,22 and a technique has been developed for the reduction of hydrocarbons by liquid cesium activated by ultrasound irradiation in the presence of ethers such as diglyme.23 The blue solutions obtained when cesium metal is dissolved in THF in the presence of [18]-crown-6 have been used to metallate a series of 1,4- or 1,5-hexadienes. The organocesium compounds have not been isolated but they have been identified by derivatization by carbonation and trimethylsilylation.24 Substituted cyclopentadienyl derivatives of sodium have also been synthesized by this method.25... 

The cesium salt of (B7C2H9)2Co (I) can be rearranged at 315°C in 24 hours to an isomeric product (III) in almost quantitative yield (6). The cyclopentadienyl derivative (A) can also be rearranged under the same conditions to a new isomer (B). The low-field doublet present in the nB NMR spectra of (I) and A is not seen in the spectra of the products. The... 

For the C-C bond-forming step coordination of an electrophilic aryl palladium halide to a cyclopentadienyl anion is assumed, followed by reductive elimination. Presumably the Pd catalyst is not involved in the C-H bond-breaking step, which is interpreted as an apparently simple deprotonation with cesium carbonate as base. The overall process is similar to the arylation of other soft nucleophiles [9]. 

SCSFO4, Cesium fluorine sulfate, 24 22 SFN, Thiazyl fluoride, 24 16 SF2HN, Imidosulfurous difluoride mercury complex, 24 14 SF3Fe06C9H5, Methanesulfonate, trifluoro-, tricarbonyl(it -cyclopentadienyl)iron-(H-), 24 161... 

Structural studies of allylmetal derivatives have also been performed [2]. In allyl compounds in ethereal solvents, the cesium ion is well solvated and an allyl anion is formed. Crystals of cyclopentadienyl rubidium and cesium, which complexed with 18-crown-6, have been isolated and analyzed by X-ray diffraction [3]. 

Closely related is the unusual mixed-hgand cesium cyclopentadienyl/penta-methy Icyclopentadienyl complex [ Cs(l 8-crown-6) 2 (fi-Cs Mc5)][ Cs( 18-crown-... 

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