Potassium bis(trimethylsilyl)amide → Tris[N,N-bis(trimethylsilyl)amide]neodymium(III)

Preparation of amine ligands was generally accomplished without exclusion of air and moisture, unless otherwise stated. All manipulations involving metal complexes were carried out under an inert atmosphere of oxygen-free UHP grade argon using standard Schlenk techniques, or under oxygen-free helium in a Vacuum Atmospheres glovebox. Chemicals were obtained from the following suppliers and used as received: Lancaster Synthesis—hexafluorobenzene, 3,5-bis(trifluoromethyl)aniline, pentafluoroaniline, 2,6-difluoroaniline, dichlorodiphenylsilane, dichlorodimethylsilane, paraformaldehyde, potassium hydroxide, 1-hexene, potassium carbonate; Aldrich—1.6 M n-butyllithium in hexane, triphenylsilane, chloroform; Strem—zirconium tetrachloride, neodymium trichloride, Fisher Scientific—methanol, ethanol, Albermarle—methylaluminoxane (30% solution in toluene); Fluka—lithium amide, 1,2-phenylene diamine, 1,8-diaminonaphthalene, 2,6-dimethylaniline, Acros—sodium sulfate, JT Baker—potassium hydroxide, NaH was obtained as a 60% dispersion in mineral oil, washed with hexane, filtered, and vacuum dried. Neodymium tris(bis(trimethylsilyl)amide) was prepared by reaction of anhydrous neodymium trichloride with three equivalents of potassium bis(trimethylsilyl)amide in refluxing THF for 24 hours, followed by low-temperature crystallization from hexane. Solvents (hexane, diethyl ether, tetrahydrofuran, toluene) were degassed and distilled from sodium benzophenone ketyl under argon. Dimethyl sulfoxide was distilled from calcium hydride under argon. Bis(triiethylsilyl)ether was distilled from potassium under argon. Benzene-d6, THF-d8, and toluene-d8 were degassed, dried over Na—K alloy, and then trap-to-trap distilled before use.