Sodium, cyclopentadienyl-, compound with 1,2-dimethoxyethane

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

TC-Cyclopentadienyl Nickel Complexes. Nickel bromide dimethoxyethane [29823-39-9] forms bis(cydopentadienyl)nickel [1271 -28-9] upon reaction with sodium cyclopentadienide (63). This complex, known as nickelocene, 7T-(C3H3)2Ni, is an emerald-green crystalline sandwich compound, mp 173°C, density 1.47 g/cm. It is paramagnetic and slowly oxidi2es in air. A number of derivatives of nickelocene are known, eg, methylnickelocene [1292-95-4], which is green and has mp 37°C, and bis( 7t-indenyl)nickel [52409-46-8], which is red, mp 150°C (87,88). 

Wilkinson et al. 12, IS) found tetrahydrofiiran and 1,2-dimethoxyethane to be most convenient and versatile solvents for the reaction of alkali metals with cyclopentadienes. Sodium cyclopentadienide is generally formed in greater than 95% yields in tetrahydrofuran (THF) and only a few per cent of by-product cyclopentene is formed. Other solvents which have been used are diethyl ether 14), xylene, /crf-butanol 15), and diethyl ether-xylene mixtures 16). A systematic study of the effect of solvent on yield in the reaction of Li, Na, and K with fluorene indicated that yield decreased in the order 1,2-dimethoxyethane > diethyl ether, % THF > dioxane > diethyl ether (77). In general, however, sodium cyclopentadienide in tetrahydrofuran has been the most widely used reagent for the preparation of other cyclopentadienyl metal compounds. (See Section II,A,la representative experimental methods are collected at the end of each section.)... 

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