Synthesis of Thorium Amide Complexes via Halide Metathesis and Transamination Procedures: X-ray Structure of Th[N(SiMe3)2]2(NMePh)2

Abstract

Reaction of ThBr4(THF)4 with 4 equiv of potassium diphenylamide in THF produces the THF adduct Th(NPh2)4-(THF) (1) in 61 % yield. Use of 4 or 5 equiv of the less bulky potassium N-methylanilide in an analogous reaction allows the isolation of the bis-THF adduct Th(NMePh)4(THF)z (2) or the salt K[Th(NMePh)s] (3), respectively. The transamination reaction of the metallacycle { [ ( M~~S~)~N I~T~( C H~S I M~~N S~M~~) )with 4 equiv of Nmethylaniline in refluxing toluene produces the four-coordinate amide species Th[N(SiMes)2]~(NMePh)2 (4). An X-ray crystal structure determination of 4 revealed a distorted tetrahedral environment about the metal center, with Th-N distances averaging 2.308 (7) A. Close approach of the methyl groups within the N-methylanilide ligands to the metal center is suggestive of an agostic interaction, with Th-C distances of 3.073 (10) and 3.064-(10) A. C stal data for 4 (at -70 "C): monoclinic space group P21/c, a = 17.091(3) A, b = 11.825(2) A, c = 16.981(3) z, , ! ? = 90.24(3)", V = 3431.9 A3, Z = 4, dcalc = 1.481 g ~m -~, R(F) = 0.0378, R,(F) = 0.0391.

Poly[[μ-dioxane-κ2O:O′-dioxane-κO-μ-diphenylamido-κ2N:N-potassium] dioxane solvate]

“…For the synthesis of transition metal diphenylamides, see: Seidel & Reichardt (1974); Villanueva et al (1994); Barnhart et al (1995); Tayebani et al (1998); Gamer et al (2001); Hitchcock et al (2002); Hevia et al (2002). For potassium diphenylamide as a catalyst in polymerization reactions, see: Longi et al (1965); Kucera & Jelinek (1959); Grogler & Windemuth (1966).…”

Bis(μ-diphenylamido-κ2N:N)bis[tris(tetrahydrofuran-κO)potassium(I)]

“…Synthesis of various transition metal diphenylamides: Seidel & Reichardt (1974); Villanueva et al (1994); Barnhart et al (1995); Tayebani et al (1998); Gamer et al (2001); Hitchcock et al (2002); Hevia et al (2002). Potassium diphenylamide as a catalyst in polymerization reactions: Longi et al (1965); Kucera & Jelinek (1959); Grogler & Windemuth (1966).…”

“…Potassium diphenylamide as a catalyst in polymerization reactions: Longi et al (1965); Kucera & Jelinek (1959); Grogler & Windemuth (1966). Synthesis of the title compound: Barnhart et al (1995); Bergstrom et al (1942); Cheshko & Goncharenko (1971);Frö hlich (1975).…”

“…One the one hand, potassium diphenylamide has been used for the synthesis of various transition metal diphenylamides, for example those of Cr (Seidel & Reichardt, 1974), Pd (Villanueva et al, 1994), Th (Barnhart et al, 1995), Nb (Tayebani et al, 1998), Y and Sm (Gamer et al, 2001), Yb (Hitchcock et al, 2002), and Re (Hevia et al, 2002). On the other hand, lactones and α,β-unsaturated cycloketones (Longi et al, 1965), octamethylcyclotetrasiloxane (Kucera & Jelinek, 1959), and isocyanates (Grogler & Windemuth, 1966) could be polymerized with potassium diphenylamide as a catalyst.…”

“…On the other hand, lactones and α,β-unsaturated cycloketones (Longi et al, 1965), octamethylcyclotetrasiloxane (Kucera & Jelinek, 1959), and isocyanates (Grogler & Windemuth, 1966) could be polymerized with potassium diphenylamide as a catalyst. Though this compound is often cited in literature (Barnhart et al, 1995;Bergstrom et al, 1942;Cheshko & Goncharenko, 1971;Fröhlich, 1975), neither an exact synthetic approach nor structural or spectroscopic data have been published. Here we present a straightforward synthesis of potassium diphenylamide and the first molecular structure of a simple potassium amide.…”