| The chemistry of all three steps of a ternary lanthanide-based catalytic system that efficiently polymerizes dienes to >98% cis-1,4-polydienes and the synthesis of new lanthanide, uranium, and silver hexafluoroacetylacetonate complexes for use as chemical vapor deposition precursors is described.; To examine the lanthanide catalytic system, well characterized precursors and intermediates were sought so their reaction chemistry could be studied in detail. Lanthanide carboxylates, {lcub}Ln[O2CC(CH3) 2Et]3{rcub}x, (Ln = La, Nd) were synthesized and Ln 2[O2CC(CH3)2Et]6[pyridine] 4, (Ln = La, Nd), and Nd2[O2CCH(C6H 5)Et]6[HO2CCH(C6H5)Et] 4 were structurally characterized. These carboxylates react with Et 2AlCl to make bimetallic Ln/Al compounds which react with one equivalent of AliBu3 to make active catalysts. In contrast the literature assumes the Et2AlCl reaction makes LnCl3 which must be activated by 10–30 equivalents of AliBu 3.; The diene catalyst reactions were also modeled by using well defined [(C5Me5)2Ln]+ coordination environments. The unusual isoprene and myrcene complexes, [(C5Me 5)2Sm]2[μ-η2:η 4-CH2CHC(Me)CH2], and [(C5 Me5)2Sm]2[μ-η2:η 4-CH2CHC(CH2)CH2CH2CHCMe 2], were obtained. New bimetallic LnAl complexes were produced, including (C5Me5)2Sm(μ-Cl)2AlMe 2, (C5Me5)2Sm(μ-Cl)2AlEt 2, (C5Me5)2Sm(THF)(μ-η 2-Et)AlEt3, and [(C5Me5)2Y(μ-Cl)(μ-R)AlR 2]x (x = 2, R = Me; x = 1, R = Et, and iBu) and the first diene-tethered tetramethylcyclopentadiene, (C5Me 4H)SiMe2(CH2CH=CHCH=CH2) and its K and Li salts, M[(C5Me4)SiMe2(CH2CH=CHCH=CH 2)], were prepared. Their reactivity with yttrium, lanthanide, and titanium reagents was explored. In addition to the modeling studies, new simple single component lanthanide initiators, LnI2 (Ln = Nd, Sm, Dy, Tm) were found for the polymerization of isoprene to high cis-1,4-polyisoprene.; The hexafluoroacetylacetonate (hfac) complexes, Ln(hfac)3(diglyme) (Ln = Nd, Sm, and Gd) were synthesized and found to react with potassium to form expected trivalent products [LnF(hfac)3K(diglyme)]2. The Eu(II) precursors, EuI2(THF)4 and {lcub}[Zr2(O iPr)9]Eu(μ-I)]{rcub}2 react with K(hfac) to also form trivalent products, Eu(hfac)3(diglyme) and [Zr2(O iPr)9]Eu(hfac)2. Ag(hfac)L complexes were synthesized (L = THF, toluene, and Me3SiCH=CH2) which oligomerized in the solid state to form extended networks. UO2 reacts with hexafluoroacetylacetone and diglyme to form three unusual uranium species; the mixed valent, [(hfac) 2UO2(μ-O)]2U(hfac)(diglyme), a complex with diglyme hydrogen bonded to a water ligand, [UO2(η1-O 2CCF3)(hfac)(H2O)2](diglyme), and a stable U(III) complex, U(hfac)3(diglyme). |
