79372-14-8Relevant academic research and scientific papers
Divalent lanthanide complexes free of coordinating anions: Facile synthesis of fully solvated dicationic [LnLx]2+ compounds
Evans, William J.,Johnston, Matthew A.,Greci, Michael A.,Gummersheimer, Tammy S.,Ziller, Joseph W.
, p. 119 - 126 (2003)
Fully-solvated, divalent lanthanide dication complexes free of coordinating anions, [LnLx]2+, in which L = MeCN, THF, have been synthesized by protonation of amide, indenyl, and pentamethylcyclopentadienyl precursors. The Sm(II) dication [Sm(THF)7]2+ was initially isolated as [Sm(THF)7][BPh4]2, (1), by protonolysis of the indenyl complex (C9H7)2Sm(THF)3 with [Et3NH][BPh4]. Compound 1 can also be obtained from (C5Me5)Sm[N(SiMe3)2] (THF)2 and [Et3NH][BPh4]. The Yb analog, [Yb(THF)6][BPh4]2, (2), was obtained from the reaction of the bimetallic [(C5Me5)Yb(THF)]2(C8 H8) with AgBPh4 and the reaction of (C5Me5)Yb[N(SiMe3)2] (THF)2 with [Et3NH][BPh4], but [YbLx]2+ is best obtained from the reaction of Yb[N(SiMe3)2]2(THF)2 with [Et3NH][BPh4]. Reaction of Yb[N(SiMe3)2]2(THF)2 with [Et3NH][BPh4] in THF followed by recrystallization from acetonitrile affords [Yb(MeCN)8][BPh4]2, (3). The seven THF molecules in 1 form a pentagonal bipyramidal ligand environment around Sm2+. Complex 2 has an octahedral Yb2+ coordination environment and 3 has a distorted square antiprismatic arrangement of MeCN ligands around Yb2+.
Reactivity of (C5Me5)2Sm with aryl-substituted alkenes: Synthesis and structure of a bimetallic styrene complex that contains an η2-arene lanthanide interaction
Evans, William J.,Ulibarri, Tamara A.,Ziller, Joseph W.
, p. 219 - 223 (2007/10/02)
(C5Me5)2Sm (I) and (C5Me5)2Sm(THF)2 (2) isomerize cis-stilbene to trans-stilbene. The stoichiometric reaction of 1 with forms [(C5Me5)2Sm]2(μ-η 2:η4-PhCHCHPh) (3). I with styrene to [(C5Me5)2Sm]2(μ-μ 2:μ4CH2CHPh) (4). In both 3 and 4, the two (C5Me5)2Sm units coordinate on opposite of the that the Sm-Sm vector bisects the bond at right angles. In each complex, phenyl carbon atoms are oriented to interact with one of the samarium centers, in 4, the Sm-C(C5Me5) distances range from 2.678 (18) to 2.847 (18) A?, the Sm-C(alkene) distances range from 2.537 (15) to 2.732 (15) A?, and two carbon atoms of the phenyl ring are 2.772 (17) and 2.850 (16) A? from one samarium atom. 3 crystallizes from hexane in space group P21212 with a = 12.156 (6) Ax?, b = 14.405 (9) A?, c = 15.628 (2) A?, and V = 2737 (2) A?3 with Z = 2 for Dcalcd = 1.24 g cm-3. 4 crystallizes from hexane in space group Pbca with a = 21.169 (4) A?, b = 17.663 (3) A?, c = 23.713 (5) A?, and V =8886 (3) A?3 with Z = 8 for Dcalcd = 1.417 g cm-3. Least-squares refinement of the model on based on 3134 observed reflections converged to a Rf= 6.2%.
