A Unique Organolanthanide Cluster Containing Bulky Cyclooctatetraenyl Ligands

Abstract

The reaction of anhydrous PrCl 3 with Li 2 (COT′′) (COT′′ ) 1,4-bis(trimethylsilyl)cyclooctatetraenyl) in THF solution afforded an unprecedented cluster-centered Pr/Li multidecker sandwich complex of composition [Pr(COT′′)] 2 -[Pr 2 (COT′′) 2 ] 2 Li 2 (THF) 2 Cl 8 (1), in which a central cube of eight Cl atoms is capped by two [Pr(COT′′)] + half-sandwich and two [Pr 2 (COT′′) 2 ] 2+ sandwich units as well as two [Li(THF)] + moieties.

Rare‐Earth Metal Bis(dimethylsilyl)amide Complexes Supported by Cyclooctatetraenyl Ligands

“…[11][12][13][14] For example, salt metathetic ex- Figure 1. Structurally characterized COT lanthanide(III) alkali metal complexes A, [5,15,16] B, [6,11,[17][18][19] C, [6,[20][21][22] D, [23] E, [24][25][26] F, [25] G, [27] H, [7] I, [11] K, [6] L, [28] M, [29] N, [30] O, [31] P. [31] Eur. J. and formation of compound R (Figure 2) was achieved straightforwardly.…”

A Chlorine‐Centered Cluster of Composition [(Me3Si)2NC(NCy)2SmCl2]5(thf)2 and a Comparison with the Heavier Ytterbium Congener [(Me3Si)2NC(NCy)2YbCl2]2(LiCl)2(thf)4

“…[9][10][11][12][13][14] The guanidinato ligand cluster provides a new idea to afford a less shielding environment.…”

New sandwich complexes of di- and trivalent ytterbium: Reduction of Yb(3+) by a bulky cyclooctatetraenyl dianion

“…More recently, bulky organosilyl-substituted COT ligands such as the 1,4-bis(trimethylsilyl)cyclooctatetraenyl dianion (¼COT 00 ) have become increasingly popular [7]. Anionic sandwich complexes of the type [Li(THF) 4 ][Ln(COT 00 ) 2 ] (Ln ¼ Ce, Pr, Sm, Y) are formed upon treatment of anhydrous LnCl 3 with 2 equiv of Li 2 (COT 00 ) [8,9]. The solid state structure of [Li(THF) 4 ][Sm(COT 00 ) 2 ] was found to consist of separated ions and thus displayed no unexpected structural features [8], whereas two very different modifications have been found for Li(DME)Tb(COT 00 ) 2 .…”

“…The solid state structure of [Li(THF) 4 ][Sm(COT 00 ) 2 ] was found to consist of separated ions and thus displayed no unexpected structural features [8], whereas two very different modifications have been found for Li(DME)Tb(COT 00 ) 2 . This compound crystallizes either in a monomeric form or as a coordination polymer depending on the solvent used for crystallization (pentane vs. toluene) [9]. Reactions of anhydrous lanthanide trichlorides with Li 2 (COT 00 ) have been shown to strongly depend on the reaction conditions and starting material ratios.…”

“…Reactions of anhydrous lanthanide trichlorides with Li 2 (COT 00 ) have been shown to strongly depend on the reaction conditions and starting material ratios. Products isolated from such reactions include not only the anionic sandwich complexes [Ln(COT 00 ) 2 ] À [8,9] and the chloro-bridged dimers [(COT 00 )Ln(m-Cl)THF)] 2 [7a,b], but also unusual cluster-centered multidecker sandwich complexes [10] as well as the triple-deckers Ln 2 (COT 00 ) 3 [2]. Besides the COT 00 ligand, other bulky cyclooctatetraenyl dianions such as 1,4-bis(triisopropylsilyl)cyclooctatetraenyl (¼COT 1,4-SiiPr3 ) [11], 1,4-bis(t-butyldimethylsilyl) cyclooctatetraenyl (¼COT TBS ) [12] and 1,3,6-tris(trimethylsilyl) cyclooctatetraenyl (¼COT 000 ) [13] have also been successfully employed in organolanthanide chemistry.…”