Probing the Salt‐Metathesis Route to Bis­(aryl)calcium Compounds: Structure of an Arylcalcate Complex

Abstract

Keywords: Alkaline earth metals / Grignard reagents / Sodium / Calcium / Salt metathesis 1,3-Diisopropoxybenzene can be selectively metalated by nBuLi or by the superbase mixtures nBuLi/NaOC(Me) 2 Et or nBuLi/KOC(Me) 2 Et to give 2,6-diisopropoxyphenyllithium (71 %), 2,6-diisopropoxyphenylsodium (61 %), or 2,6-diisopropoxyphenylpotassium (59 %) as isolated products. The attempted synthesis of bis(2,6-diisopropoxyphenyl)calcium by the salt metathesis route using 2,6-diisopropoxyphenylsodium and CaI 2 gave an undefined mixture of products, whereas the attempted synthesis of bis(2,6-diisopropoxy-

Alkali-Metal-Mediated Synergistic Effects in Polar Main Group Organometallic Chemistry

“…It exists as a linear coordination polymer in the crystal (Figure ). The authors make an important general point in this paper, namely, “the exchange of different anions and cations may lead to complex mixtures of compounds in which certain combinations might be favored, or in the case that the product is obtained by crystallization, the least soluble species will be obtained.”…”

“…93 The importance of the identity of the alkali metal in metathesis reactions is brought home in the attempted synthesis of bis(2,6-diisopropoxyphenyl)calcium from treatment of 2,6-diisopropoxyphenylsodium with calcium iodide. Whereas this reaction gave an undefined mixture of products, switching to using the heavier alkali metal congener 2,6diisopropoxyphenylpotassium afforded the calciate complex (94), which is reported to be the first arylcalciate complex of type [M] + [Ar 3 Ca] − to have been structurally characterized. It exists as a linear coordination polymer in the crystal (Figure 22).…”

“…It exists as a linear coordination polymer in the crystal (Figure 22). 94 The authors make an important general point in this paper, namely, "the exchange of different anions and cations may lead to complex mixtures of compounds in which certain combinations might be favored, or in the case that the product is obtained by crystallization, the least soluble species will be obtained." (101), alkaline-earth metal complexes complexes have been made by cocomplexing the Group 1 metal species with its Group 2 counterpart in THF (PFTB = perfluoro-tert-butoxide).…”

Trimethylsilylmethylcalcium Iodide, an Easily Accessible Grignard-Type Reagent of a Heavy Alkaline Earth Metal

“…This kind of complex can be stabilized by internal Lewis bases being part of the silyl side arms . Bis­(trimethylsilyl)­methyl derivatives of calcium, strontium, and barium were also prepared employing this strategy, but the stoichiometry has to be maintained in order to avoid the formation of potassium trialkylcalciates . The transmetalation of organozinc derivatives yields the corresponding zincates as contact ion pairs with bridging alkyl groups; however, dialkylcalcium has not been isolated via this metal–metal exchange route.…”

2-Imino-2,3-dihydrobenzoxazole—a useful platform for designing rare- and alkaline earth complexes with variable di- and trianionic O,N,N, ligands

“…with the values previously measured in Ca-phenolate complexes. [36][37][38][39][40][41][42] In 3, the calcium ion is bound only with the amido nitrogens and the Ca-N distances are 2.348(2) Å. The Na-N bonds in 3 are noticeably different.…”