Étude physico-chimique des complexes tétraéthylzincate de calcium, strontium et baryum

Alkyl Abstraction from a Trialkylyttrium Complex [YR3(thf)2] (R = CH2SiMe3) Using a Group‐13 Element Lewis Acid ER3 (E = B, Al, Ga, In) – Structural Characterisation of the Ion Pair [YR2(thf)4]+[GaR4]– and of ER3 (E = B, Al, Ga)

“…[10] NMR spectroscopic analysis of these compounds showed that all alkyl groups are chemically and magnetically equivalent on the NMR timescale and an equilibrium between neutral alkyl complexes, "ate" complexes, contact ion pairs and solvent separated ions was proposed in the literature. [10][11][12] A further example for solvent dependence of the structures and for intra-/intermolecular exchange was reported for [La(η 5 -(E = Ga, 2b; In, 2c), as was observed for 1a. The peaks arising from the cationic yttrium species are similar in all three cases, implying only weakly coordinating anions.…”

Zinc Alkyls, Edward Frankland, and the Beginnings of Main-Group Organometallic Chemistry

“…Compounds of the type MZn(C 2 H 5 ) 4 (M ) Ca, Sr, Ba) also are known. 119 Finally, there are some interesting compounds that contain a [C 2 H 5 Zn] + cation. 120 When a benzene solution containing equimolar amounts of (C 2 H 5 ) 2 Zn, (C 2 H 5 ) 3 Al, the and 1,1,2-cryptand C is prepared, a small dense liquid phase separates that contains C 2 H 5 ZnC + and (C 2 H 5 ) 4 …”

Structural Organozinc Chemistry

“…In early days structural investigations on organozincates were limited to physicochemical measurements. For example, the calcium, strontium and barium tetraethylzincates were studied by 1 H NMR and UV spectroscopy and by cryoscopic molecular-weight determinations 38 . These solution studies provided limited information, contrary to the more recently combined NMR and Raman spectroscopic and EXAFS studies on 'highly coordinated' heteroleptic organozincates [Me 3 ZnR]Li 2 (R = CN or SCN).…”