Organocesium compounds

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... 

Carbanion equivalents with anion stabihzing groups are prepared by desilylation of the corresponding materials with cesium fluoride [9-15]. In Scheme 2.6 treatment of aryltrimethylsilanes with cesium fluoride affords carbanion equivalents which add to the carbonyl compounds. The reactive species are not simple organocesium compounds but react as nucleophilic carbanion equivalents. 

As the first transmetalation reaction, for example, organosodium compounds (1858) [20], organopotassium compounds (1858) [20], organonibidium compounds (1926) [21], organocesium compounds (1926) [21] and organothallium compounds (1870) [22], etc. are cited. 

---