1070-89-9Relevant articles and documents
Ln(II)/Pb(II)-Ln(III)/Pb(0) Redox Approach toward Rare-Earth-Metal Half-Sandwich Complexes
Bienfait, André M.,Wolf, Benjamin M.,T?rnroos, Karl W.,Anwander, Reiner
, p. 5734 - 5744 (2015)
The divalent bis(trimethylsilyl)amide complexes Ln[N(SiMe3)2]2(THF)2 (Ln = Sm, Yb) react with 0.5 equiv of lead(II) pentamethylcyclopentadienide, Cp?2Pb (Cp? = C5Me5), in n-hexane to form the half-sandwich complexes Cp?Ln[N(SiMe3)2]2 (Ln = Sm, Yb) in almost quantitative yield. The same reaction performed with Eu[N(SiMe3)2]2(THF)2 resulted in the cocrystallization of the sandwich complex Cp?2Eu[N(SiMe3)2] and homoleptic Eu[N(SiMe3)2]3. The divalent bis(dimethylsilyl)amide complexes Ln{[μ-N(SiHMe2)2]2Ln[N(SiHMe2)2](THF)}2 (Ln = Sm, Yb) react with 1.5 equiv of Cp?2Pb in n-hexane/THF to form the half-sandwich complexes Cp?Ln[N(SiHMe2)2]2(THF) (Ln = Sm, Yb). The corresponding europium reaction did not provide any crystalline material. Treatment of divalent Eu[N(SiMe3)2]2(THF)2 with 2 equiv of 3-tert-butyl-5-methylpyrazole (HpztBu,Me) in THF generates [(pztBu,Me)Eu(μ-pztBu,Me)(THF)2]2. Oxidation of the europium(II) pyrazolate complex with 1 equiv of Cp?2Pb in THF afforded Cp?Eu(μ-pztBu,Me)2(THF)2. The tetramethylaluminate compounds {Ln(AlMe4)2}n (Ln = Sm, Yb) react with 0.5 equiv of PbCp?2 in n-hexane to produce mixtures of half-sandwich and metallocene complexes Cp?Ln(AlMe4)2 and [Cp?2Ln(μ-AlMe4)]2, respectively. The attempted oxidation of {Eu(AlMe4)2}n led to the formation of {Cp?Eu(AlMe4)}, which could be crystallized from THF to give polymeric {Cp?Eu(μ-AlMe4)(THF)3}n. The reaction of chloro-contaminated {Sm(AlMe4)2}n with 2 equiv of HCp? performed in THF led to the isolation of the unexpected mixed chloride methylidene complex [Cp?3Sm3(μ2-Cl)3(μ3-Cl)(μ3-CH2)(THF)3]. Reacting {Yb(AlEt4)2}n with 0.5 equiv of Cp?2Pb in n-hexane gave a mixture of products, from which Cp?2Yb(AlEt4) was identified. Performing the same reaction in toluene in the presence of diethyl ether resulted in the formation of the divalent metathesis product Cp?Yb(AlEt4)(Et2O)2.
Monodentate coordination of the normally chelating chiral diamine (R,R)-TMCDA
Ojeda-Amador, Ana I.,Martínez-Martínez, Antonio J.,Kennedy, Alan. R.,Armstrong, David R.,O'Hara, Charles T.
, p. 324 - 327 (2017)
After isolating an unusual binuclear, but monosolvated NaHMDS complex [{(R,R)-TMCDA}·(NaHMDS)2]∞ which polymerises via intermolecular electrostatic Na...MeHMDS interactions, further (R,R)-TMCDA was added to produce the dis
Migration of trimethylsilyl group in the reaction of sodium bis(trimethylsilyl)amide with bromobenzene
Lis,Tsyrendorzhieva,Albanov,Rakhlin,Voronkov
, p. 1451 - 1453 (2013)
The reaction of sodium bis(trimethylsilyl)amide with bromobenzene gave a mixture of N,N-bis-(trimethylsilyl)aniline and N,2-bis(trimethylsilyl)aniline, the latter being a rearrangement product formed via 1,3-migration of trimethylsilyl group from the nitrogen atom to the ortho-carbon atom in the benzene ring.
Method of continuous variation: Characterization of alkali metal enolates using 1h and 19F NMR spectroscopies
Tomasevich, Laura L.,Collum, David B.
, p. 9710 - 9718 (2014)
The method of continuous variation in conjunction with 1H and 19F NMR spectroscopies was used to characterize lithium and sodium enolates solvated by N,N,N,N-tetramethylethyldiamine (TMEDA) and tetrahydrofuran (THF). A strategy developed using lithium enolates was then applied to the more challenging sodium enolates. A number of sodium enolates solvated by TMEDA or THF afford exclusively tetramers. Evidence suggests that TMEDA chelates sodium on cubic tetramers.
New UIII and UIV silylamides and an improved synthesis of NaN(SiMe2R)2 (R = Me, Ph)
Mansell, Stephen M.,Perandones, Bernabé Fernandez,Arnold, Polly L.
, p. 2814 - 2821 (2010)
It is shown that the deprotonation of bulky amides such as HN(SiMe 2Ph)2 may be accelerated by the use of catalytic quantities of an alkali metal tert-butoxide salt, affording, for example, overnight syntheses of NaN(SiMe2Ph)2. The new uranium(IV) and uranium(III) complexes [U{N(SiMe2H)2}4] and [U{N(SiMe2Ph)2}3] are both accessible from the Group 1 salts of the amides and UI3(thf)4 in thf. The choice of sodium or potassium salt made no difference to the reaction outcome. Both exhibit Weak interactions between uranium and with silyl-H or silyl-Ph groups in the solid-state.
