Studies on systems of salts and mixed solvents 35—²⁷ Al NMR investigations of AlCl₃‐water‐N,N‐dimethylformamide solutions using the solid‐state MAS technique

Abstract

Conventional liquid-state "A1 NMR spectra of concentrated solutions of the AIC1,-water-N,Ndimethyl-N-Dimethylformamide formamide system contain comparatively broad non-structured lines. Application of MAS leads to a reduction in the line width and a structuring of the spectra. This allowed the experimental determination of the chemical shifts of (AI(H,O), -,(DMF)$+ (x = 0-6) mixed-ligand complexes. The investigations demonstrate an example of the applicability to liquids of the NMR MAS technique, which was originally developed for solids. They underline the existence, in a reduced form, of 'solid-type' interactions within the investigated solutions. KEY WORDS "A1 NMR spectroscopy MAS technique Concentrated electrolyte solutions

The influence of aluminium cations on electrocarboxylation processes in undivided cells with Al sacrificial anodes

“…The concentration of Al(III) in solution was calculated from the consumed charge according to the anodic reaction (1), assuming a 100% current efficiency. In solution, Al(III) forms solvate complexes in which the central metal is always hexacoordinated ðAlðSÞ 3þ 6 , where S stands for a solvent molecule) [15][16][17][18][19]. Al þ 6S AlðSÞ 3þ…”

“…Of course, the presence of solvated Al cations change the cathodic reaction mechanism but the overall process leads to a carbanion, which readily reacts with CO 2 to give the carboxylated product (Eqs. (19) and (20)). …”

Electrocarboxylation of aromatic ketones: Influence of operative parameters on the competition between ketyl and ring carboxylation

“…According to various literature reports [23][24][25][26], in coordinating solvents, Al(III) forms solvate complexes in which the central metal is hexacoordinated (AlðSÞ 3þ 6 , where S stands for a solvent molecule). In the case of ketones, the solvated ions may interact with the starting ketone and/or its radical anion, leading to an adduct [ArC(R)O] ÅÀ AlðSÞ 3þ 5 in which the negative charge in the ketyl radical anion is at least partially neutralised.…”