Synthesis and Structure of a Dimeric Alkyldibariumtriszincate with a Tetraanionic Triszincate Ligand and a Unique Central Ba4Zn2C6 Moiety

Abstract

Transmetalations of zincates succeed only after activation of the barium metal. Dialkylbarium, the initial product, metalates the zincate anions which are still present in solution and leads to the formation of tetraanionic tris(zincate) ligands, which sterically shield the Ba−C bonds of a Ba4Zn2C6 cage (see structure).

Not Just Heavy “Grignards”: Recent Advances in the Organometallic Chemistry of the Alkaline Earth Metals Calcium, Strontium and Barium

“…This highly reactive substrate reacts immediately with subsequently added metal and excess zincate to form the unique barium cubane (15; Figure 10) with extrusion of tetramethylsilane. [45] This distorted, face-sharing double cube possesses agostic interactions between the methylene groups and the nearby barium centers, in addition to metal-carbon σ-bonds within the range observed for other σ-bonded compounds.…”

Chasing Multiple Bonding Interactions between Alkaline‐Earth Metals and Main‐Group Fragments

“…Lewis‐acid stabilization might also emerge as a viable concept for Ae alkylidenes, in particular due to the fact that related AlMe 3 ‐capped Ae alkyls are already well established (tetraalkylaluminates [Ae(AlR 4 ) 2 ] n , see Introduction) . Using dialkylzinc ZnR 2 instead of AlR 3 as a stabilizing Lewis acid it was indeed possible to access the heterobimetallic barium/zinc alkylidene [Ba 4 Zn 2 (CHSiMe 3 ) 6 {Zn(CH 2 SiMe 3 ) 2 } 4 ] ( 12 ), featuring a central Ba 4 Zn 2 C 6 cage in the solid state (Scheme ) . Compound 12 was obtained in 76 % yield from a reaction of the corresponding barium zincate [Ba{Zn(CH 2 SiMe 3 ) 3 } 2 ] with barium metal under application of ultrasound, nicely underlining the feasibility of this concept.…”

Alkaline Earth Organometallics

“…401 The Figure 95 The structure of the calcium-lithium complex CaLi 2 (oepg)(THF) 3 181. 401 The Figure 95 The structure of the calcium-lithium complex CaLi 2 (oepg)(THF) 3 181.…”