Ligand and Metal Effects on the Formation of Main‐Group Polyhedral Clusters

Abstract

Ein Lithiumcluster mit eingeschlossenem Hydridion, [Li8(H)m(hpp)6]n+[X]−n, entsteht als Hauptprodukt bei der Umsetzung des nichtaromatischen Heterocyclus 1,3,4,6,7,8‐Hexahydro‐2H‐pyrimido[1,2‐a]pyrimidin (hppH) mit ZnMe2 (m=n=1, X=[ZntBu3]; Kation siehe Bild). Ähnliche Strukturen könnten auch in anderen Polylithium‐Architekturen vorliegen. Ersetzt man ZnMe2 durch AlMe3, so erhält man ein Produkt ohne Hydrideinschluss (m=0, n=2, X=[Li(Me2AltBu2)2]).

A Hydrocarbon‐Soluble Lithium Hydride Complex

“…2.03-2.04 ), [1] close to those of [[{(Me 3 Si) 2 N}AlH 2 Li] 3 (LiH)], [11] and comparable to those of the interstitial Li-H compounds [L 6 HLi 8 ] + and [L 6 HLi 7 ]. [12,13] In addition, comparable short Li···H aliphatic contacts are found in 3, the shortest one being around 2.0 , and similar interactions are observed in 2. Four shorter Li-H contacts of 1.81(4)-1.83(4) are measured to Li1 and Li2 of the outer tetrahedra.…”

A Hydrocarbon‐Soluble Lithium Hydride Complex

“…[2,10] Some remarkable examples include mixed metal systems such as [[{(Me 3 Si) 2 N}AlH 2 Li] 3 (LiH)] having a central distorted (LiH) 4 cube featuring one hydride moiety solely bound to Li cations. [12,13] Active forms of alkali metal hydrides MH (M = Li, Na, K) have been obtained from mixtures of metal alkoxides and alkyl metal compounds in the presence or absence of dihydrogen or from alkyl metal compounds and silanes. [12,13] Active forms of alkali metal hydrides MH (M = Li, Na, K) have been obtained from mixtures of metal alkoxides and alkyl metal compounds in the presence or absence of dihydrogen or from alkyl metal compounds and silanes.…”

Well‐Defined, Nanometer‐Sized LiH Cluster Compounds Stabilized by Pyrazolate Ligands

“…[7a] For Group 1 metals, the majority of hydride complexes are mixed element hydrides that are better described as "-ate" complexes, and the unique mixed Al/Li example [({(Me 3 Si) 2 N}AlH 2 Li) 3 (LiH)] contains one hydride that is only bound to Li centers. [8] Furthermore, cationic [L 6 Li 8 H] + (L = chelating anionic ligand) and neutral [L 6 Li 7 H] complexes with an interstitial hydride ion have been prepared, [9,10] and the structure of the large mixed lithium alcoholate/hydride cluster [(tBuOLi) 16 (LiH) 17 ] was reported. [11] We have recently used the silane method to synthesize hydrocarbon-soluble [(LLi) 4 (LiH) 4 ] (L= DipNPPh 2 , Dip = 2,6-iPr 2 C 6 H 3 ), which contains a central (LiH) 4 cube.…”

“…[14] Several related examples of cationic [L 6 Li 8 H] + (L = chelating anionic ligand) and neutral [L 6 Li 7 H] complexes have previously been studied by Wheatley and coworkers. [9,10] The structure of [(pz) 10 [14] and the salt [Li(thf) [14] are based on lattice cutout B (Figure 2 Figure S12). For the [(pz) 12 [14] which suggests that this is the most reactive site of the complex.…”