Uranium chlorotris

Chlorotris(//-cyclopentadienyl)uranium(IV) is an oxygen-sensitive brown solid. It can be handled in air for brief periods of time with minimal oxidation, which is evidenced by darkening of the color. The compound is soluble in ethereal and aromatic solvents but only sparingly soluble in aliphatic hydrocarbons. Solutions are exceedingly air-sensitive. The nmr spectrum in benzene exhibits a sharp singlet 9.6 ppm to high field of the solvent (r 12.4). The infrared spectrum (Nujol mull) exhibits typical 7t-cyclopentadienyl bands at 1013 (m) and 784 (s) cm i. Oxidation is evidenced by the appearance of the antisymmetric v(OUO) stretch of the uranyl group at 930 cm-i. 

Method II. A 200-mL, single-necked, round-bottomed flask containing a magnetic stirring bar is charged with 4.68 g (10 mmol) of chlorotris (> -cyclopentadienyl)uranium(IV), 100 mL of freshly distilled THF, and 0.79 g (10 mmol) of (diethylamido)lithium. The red solution is stinted for 24 h at room temperature. The solvent is then removed under vacuum. The residue obtained is dissolved in 100 mL of toluene, and the solution is Altered to separate the lithium chloride, which is washed with toluene until the washings are colorless. The solvent is then removed under vacuum, giving a red solid that is dried for 2 h under vacuum at room temperature. Yield 4.29 g (85%). 

UClCijHij, Uranium(IV), chlorotris(Ti -cyclopentadienyl)-, 28 301 UCl2Si2C22H42, Uranium(IV), bis(ii -l,3-bis(trimethylsilyl)cyclopentadienyl]di-chloro-, 27 174... 

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