5384-63-4Relevant articles and documents
Facile Reversible Benzophenone Insertion into Rare-Earth Metal Pyrazolate Complexes
Werner, Daniel,Deacon, Glen B.,Junk, Peter C.,Anwander, Reiner
, p. 3419 - 3428 (2017)
Treatment of the homoleptic CeIV pyrazolate complex [Ce(Me2pz)4]2 (Me2pz = 3,5-dimethylpyrazolato) with benzophenone (bp) led to the formation of an Me2pz-substituted diphenylmethoxy-(N,O)-chelating ligand (pdpm), possibly metal-templated through initial coordination of bp to the cerium atom and subsequent bp insertion into the Ce–N(Me2pz) bond. This coordination/insertion process was shown to be reversible, leading to a complex sequence of equilibria involving multiple degrees of insertion/de-insertion and association/dissociation. The dependency on temperature and the amount of bp of all equilibria was revealed, with insertion/association of bp being favored at low temperatures and de-insertion/dissociation preferentially occurring at elevated temperatures. Such sets of equilibria were also observed for the treatment of trivalent complexes [Ln(Me2pz)3(thf)]2 (Ln = La, Ce, Lu) with bp. Through structural analysis, the trivalent complexes were shown to be less effective in the bp-to-pdpm conversion than the CeIV derivative, giving direct evidence of how an increase in rare-earth Lewis acidity aids in ketone anchorage and concomitant conversion. The observed equilibria seem to also apply to the more illustrious organocerium systems. The conversion of bp into the corresponding tertiary alcohol by the routinely employed reagent CeCl3/nBuLi is the most selective when termination of the reaction by hydrolysis is performed at lower temperatures, with a reagent ratio bp/CeCl3/nBuLi of 1:1:1.
I-Pr2NMgCl·LiCl Enables the Synthesis of Ketones by Direct Addition of Grignard Reagents to Carboxylate Anions
Colas, Kilian,Dos Santos, A. Catarina V. D.,Mendoza, Abraham
supporting information, (2019/10/08)
The direct preparation of ketones from carboxylate anions is greatly limited by the required use of organolithium reagents or activated acyl sources that need to be independently prepared. Herein, a specific magnesium amide additive is used to activate and control the addition of more tolerant Grignard reagents to carboxylate anions. This strategy enables the modular synthesis of ketones from CO2 and the preparation of isotopically labeled pharmaceutical building blocks in a single operation.
LITHIUM-POROUS METAL OXIDE COMPOSITIONS AND LITHIUM REAGENT-POROUS METAL COMPOSITIONS
-
Paragraph 0057, (2014/10/29)
The invention relates to lithium reagent-porous metal oxide compositions having RLi absorbed into a porous oxide. In formula RLi, R is an alkyl group, an alkenyl group, an alkyny group, an aryl group, an alkaryl group, or an NR1R2 group; R1 is an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an alkaryl group; and R2 is hydrogen, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, and an alkaryl group. The preparation and use of lithium reagent-porous metal oxide compositions having RLi absorbed into a porous oxide compositions are also described.
