Halide, Amide, Cationic, Manganese Carbonylate, and Oxide Derivatives of Triamidosilylamine Uranium Complexes

Treatment of the complex [U(Tren(TMS))(Cl)(THF)] [1, Tren(TMS) = N(CH2CH2NSiMe3)(3)] with Me3SiI at room temperature afforded known crystalline [U(Tren(TMS))(1)(THF)] (2), which is reported as a new polymorph. Sublimation of 2 at 160 degrees C and 10(-6) afforded the solvent free dimer complex [{U(Tren(TMS))(mu-I)}(2)] (3), which crystallizes in two polymorphic forms. During routine preparations of 1, an additional complex identified as [U(Cl)(5)(THF)][Li(THF)(4)] (4) was isolated in very low yield due to the presence of a slight excess of [U(Cl)(4)(THF)(3)] in one batch. Reaction of 1 with one equivalent of lithium dicyclohexylamide or bis(trimethylsilyl)amide gave the corresponding amide complexes [U(Tren(TMS))(NR2)] (5, R = cyclohexyl; 6, R = trimethylsilyl), which both afforded the cationic, separated ion pair complex [U(Tren(TMS))(THF)(2)][BPh4] (7) following treatment of the respective amides with Et3NH center dot BPh4. The analogous reaction of 5 with Et3NH center dot BAr4f [Ar-f = C6H3-3,5-(CF3)(2)] afforded, following addition of 1 to give a crystallizable compound, the cationic, separated ion pair complex [{U(Tren(TMS))(THF)}(2)(mu-Cl)][BAr4f] (8). Reaction of 7 with K[Mn(CO)(5)] or 5 or 6 with [HIVIn(CO)(5)] in THF afforded [U(Tren(TMS))(THF)(mu-OC)Mn(CO)(4)] (9); when these reactions were repeated in the presence of 1,2-dimethoxyethane (DME), the separated ion pair [U(Tren(TMS))(DME)][Mn(CO)(5)] (10) was isolated instead. Reaction of 5 with [HMn(CO)(5)] in toluene afforded [{U(Tren(TMS))(mu-OC)(2)Mn(CO)(3)}(2)] (11). Similarly, reaction of the cydometalated complex [U[N(CH2CH2NSiMe2But)(2)((CH2CH2NSiMeBuCH2)-C-t)}] with [HMn(CO)(5)] gave [{U(Tren(DMSB))(mu-OC)(2)Mn(CO)(3)}(2)] [12, Tren(DMSB) = N(CH2CH2NSiMe2But)(3)]. Attempts to prepare the manganocene derivative [U(Tren(TMS))MnCp2] from 7 and K[MnCp2] were unsuccessful and resulted in formation of [{U(Tren(TMS))}2(14-0)] (13) and [MnCp2]. Complexes 3-13 have been characterized by X-ray crystallography, H-1 NMR spectroscopy, FTIR spectroscopy, Evans method magnetic moment, and CHN microanalyses.