Triiodotetrakis pyridine uranium, Ul3 py

In the glove box, 8.1 g (34.0 mmol) of freshly amalgamated uranium turnings (see Section 55.A) are placed in an oven-dried, 250-mL, one-neck Schlenk reaction vessel, along with a 1-in. Teflon-coated magnetic stirring bar, and 200 mL of distilled, degassed pyridine. The reaction vessel is removed from 

Triiodotetrakis(pyridine)uranium is an extremely air- and moisture-sensitive, purple-black solid, which may be stored for months in the absence of air and moisture. It is appreciably soluble in pyridine approximately 17 g in 30 mL pyridine at 20°C. The compound is sparingly soluble in benzene and toluene, but readily dissolves in THF with ligand substitution. Freshly prepared samples of UIa(py)4 in benzene-d show three broad NMR resonances (250 MHz, 20°C) at 5 17.8, 15.4, and 12.0 in a 2 1 2 ratio corresponding to the protons of coordinated pyridine. The IR spectrum, recorded as a Nujol mull between KBr plates, has absorptions at 1597(m), 1304(w), 1215(m), 1169(w), 1150(m), 1061(m), 1034(m), 999(m), 976(w), 756(s), 725(w), 698(s), 621(s), and 425(w) cm . 

Sodium bis(trimethylsilyl)amide is an air- and moisture-sensitive white solid which is soluble in toluene, diethyl ether, THF, and pyridine. An alternative procedure for its synthesis may be found in an earlier volume of this series.  

In the glove box, 18.2 g (99.3 mmol) of NaN(SiMe3)2 are placed in an oven-dried, 2S0-mL Erlenmeyer flask, 100 mL of THF are added, and the solution is gently swirled until all of the sodium bis(trimethylsilyl)amide is 

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