Grignard reagents as powders : preparation and reactivity

Tris[2-(2-methoxyethoxy)ethyl]amine

“…The complexes are thermally stable ( Table 2; with permission of Elsevier Science, this table was reproduced from ref. 32) and have reactivities comparable to the conventional Grignard reagents. Selective additions to aldehydes in the presence of ketones were observed, and the reactions can be performed in hydrocarbon solvents.…”

“…TDA-1 has also found applications in nucleoside chemistry. The 3,7-dideazapurine deoxyribofuranoside derivative (32) was prepared in 90% yield by the reaction of 3, 7-dideazapurine (30) and chlorofuranose (31) with 2.5 mol % TDA-1 and KOH in acetonitrile (eq 11). 15 In a similar fashion, 1,7-dideazapurine (33) and 5-aza-7-deazaguanine (35) were reacted with 31 to give deoxyribofuranosides (34) 16 and (36) 17 , in 78% and 88% yield, respectively (eqs 12 and 13).…”

“…Another unique application of TDA-1 was its use as a chelating agent to complex Grignard reagents. 32 The complexes are powders, stable under nitrogen, and can be titrated and used as Grignard reagents. The complexes were generated by the addition of an etheral solution of TDA-1 to two molar equivalents of the Grignard reagent.…”

Alkaline Earth Metal Template (Cross‐)Coupling Reactions with Hybrid Disila‐Crown Ether Analogues

“…From the perspective of Si−O bond activation, weakening of Si−O bonds is of considerable significance regarding the conversion of silicates to silanes. Especially dicatecholato‐silicate(IV) complexes are frequently used as precursors for either silane synthesis or functionalization of various organic molecules . Most recently, a collaborative research of Ollivier and co‐workers together with Fensterbank and co‐workers demonstrated a new synthesis for ketones, in this context employing acyl chlorides …”

MeZnOMe‐mediated reaction of aldehydes with Grignard reagents: A glance into nucleophilic addition/Oppenauer oxidation pathway

“…Early in 1985, Screttas and co‐workers observed that the presence of lithium 2‐ethoxyethoxide could dramatically improve the solubility of Grignard reagents in aromatic hydrocarbon solvents. Similarly, the presence of magnesium 2‐ethoxyethoxide could not only reduce the interaction of alkyl lithium reagents with tetrahydrofuran (THF), allowing their direct preparation in THF solution, but also promote halogen–metal exchange reaction to generate a new Grignard reagent . Remarkably, the presence of aminoalcohol could dramatically improve the nucleophilicity of diorganozinc reagents to realize a quick and asymmetric addition to carbonyls .…”