The reaction of excess, oxide-free amalgamated uranium metal turnings with elemental iodine or bromine in coordinating solvents at 0-degrees-C provides dark purple UI3(THF)4 (1), royal blue UBr3(THF)4 (2), purple UI3(dme)2 (3), or jet black UI3(PY)4 (4) in 65-80% isolated yield (THF = tetrahydrofuran, dme - 1,2-dimethoxyethane, py = pyridine). Neptunium and plutonium metal also react cleanly with elemental iodine in aprotic coordinating solvents to give yellow-orange NpI3(THF)4 (5), Off-white PuI3(THF)4 (6), and gray PuI3(PY)4 (7) in 80-90% isolated yields. These organic-solvent-soluble Lewis base adducts of early actinide tribalides are precursors to a variety of inorganic and organometallic actinide complexes. Reaction Of AnI3(THF)4 complexes (U, Np, Pu) 1, 5, and 6 in THF solution with 3 equiv of sodium bis(trimethylsilyl)amide provides the volatile, solvent-free tris-(silylamide) complexes An[N(SiMe3)2]3 [An = U (8), Np (9), Pu (10)] in 80-90% yields. The neptunium and plutonium silylamides are the first examples of homoleptic amido complexes of the transuranic elements. Compounds 1-10 have been fully characterized by variable-temperature proton NMR,IR,UV/vis/near-IR, thermal gravimetric, nd elemental analyses. Single-crystal X-my diffraction data for 1 revealed a pentagonal bipyramidal coordination geometry about the central uranium atom with two axial iodide ligands (U-I = 3.111(2) angstrom (average)) and one equatorial iodide ligand (U-I = 3.167(2) angstrom). All four THF ligands lie in the equatorial plane with an average U-0 distance of 2.52(1) angstrom. Crystal data for 1 (at 23-degrees-C) : monoclinic space group P2(1)/c, with a = 8.750(3) angstrom, b = 16.706(16) angstrom, c = 17.697(7) angstrom, beta = 93.64(3)-degrees, V = 2582 angstrom3, d(calc) = 2.33 g CM-3, Z = 4.