Building blocks for the chemistry of perfluorinated alkoxyaluminates [Al{OC(CF3)3}4]−: simplified preparation and characterization of Li+–Cs+, Ag+, NH4+, N2H5+ and N2H7+ salts

A series of group 1 hydrocarbon-soluble donor free aluminates [AM( t BuDHP)(TMP)Al( i Bu) 2 ] (AM=Li, Na, K, Rb) have been synthesised by combining an alkali metal dihydropyridyl unit [(2-t BuC 5 H 5 N)AM)] containing a surrogate hydride (sp 3 CÀ H) with [( i Bu) 2 Al(TMP)]. These aluminates have been characterised by X-ray crystallography and NMR spectroscopy. While the lithium aluminate forms a monomer, the heavier alkali metal aluminates exist as polymeric chains propagated by non-covalent interactions between the alkali metal cations and the alkyldihydropyridyl units. Solvates [(THF)Li-( t BuDHP)(TMP)Al( i Bu) 2 ] and [(TMEDA)Na( t BuDHP)(TMP)Al( i Bu) 2 ] have also been crystallographically characterised. Theoretical calculations show how the dispersion forces tend to increase on moving from Li to Rb, as opposed to the electrostatic forces of stabilization, which are orders of magnitude more significant. Having unique structural features, these bimetallic compounds can be considered as starting points for exploring unique reactivity trends as alkali-metal-aluminium hydride surrog [ATES].

Section: Resultsmentioning

confidence: 99%

“…Crystallographically characterised compounds containing both rubidium and aluminium in a bimetallic complex are rare in the literature. [ 24a , 24b , 24c , 24d , 24e , 24f ]…”

Section: Resultsmentioning

confidence: 99%

Hydrocarbon Soluble Alkali‐Metal‐Aluminium Hydride Surrog[ATES]

Banerjee

Macdonald

Orr

et al. 2022

“…[38] Its formal reduction potential lies at 1.29 Vv ersus Fc/Fc + in ortho-difluorobenzene( o-DFB), hence sufficiently high to oxidize 1 to ad ication. Thel arge Al-based weakly coordinating counterion Al(OR F ) 4 ] À (R F = C(CF 3 ) 3 ) [39] serves to stabilize generated reactive cationic species. [40][41][42][43][44] Indeed, treatment of 1 with one or two equivalents of 3 in o-DFB furnished cation radical 1C + + andd ication 1 2 + + as deeplyr ed-and blue-coloreds olutions, respectively.L ayeringo ft he obtained reactionm ixtures with pentanea fforded singlec rystalss uitable for X-ray diffraction analysisofb oth salts.…”

Section: Resultsmentioning

confidence: 99%

Cations and Anions of Dibenzo[a,e]pentalene and Reduction of a Dibenzo[a,e]pentalenophane

Hermann

Böttcher

Schorpp

et al. 2021

Self Cite

Dibenzo[a,e]pentalene (DBP) is a non‐alternant conjugated hydrocarbon with antiaromatic character and ambipolar electrochemical behavior. Upon both reduction and oxidation, it becomes aromatic. We herein study the chemical oxidation and reduction of a planar DBP derivative and a bent DBP‐phane. The molecular structures of its planar dication, cation radical and anion radical in the solid state demonstrate the gained aromaticity through bond length equalization, which is supported by nucleus independent chemical shift‐calculations. EPR spectra on the cation radical confirm the spin delocalization over the DBP framework. A similar delocalization was not possible in the reduced bent DBP‐phane, which stabilized itself by proton abstraction from a solvent molecule upon reduction. This is the first report on structures of a DBP cation radical and dication in the solid state and of a reduced bent DBP derivative. Our study provides valuable insight into the charged species of DBP for its application as semiconductor.

“…Handling of all compounds as well as substrates used requires strictly anhydrous conditions which were provided by Ar‐filled glovebox (O 2 <0.1 ppm) and working using Schlenk technique. Ag[Al(OR F ) 4 ] was obtained according to literature methods [37] . Anhydrous CoCl 2 was obtained by thermal dehydration of CoCl 2 ⋅ 6 H 2 O (Chempur, p.a .)…”

Section: Methodsmentioning

confidence: 99%

“…Ag[Al(OR F ) 4 ] was obtained according to literature methods. [37] Anhydrous CoCl 2 was obtained by thermal dehydration of CoCl 2 • 6 H 2 O (Chempur, p.a.) at 200 °C followed by overnight treatment with SOCl 2 .…”

Section: Methodsmentioning

confidence: 99%

Stabilization of Potent Co(II)‐based Lewis Acids with Weakly Basic Ligands

Jadwiszczak

Malinowski

2022

Self Cite

Pairing cations with weakly coordinating anions (WCAs) often renders them highly Lewis-acidic and extremely reactive. Although these features are often desirable, excessive reactivity of a cation may lead to decomposition of solvents or WCAs, hindering isolation, storage and practical use of such species. In an attempt to mitigate the problem, we introduce a series of readily available novel Co(II)-WCA salts with the metal center stabilized by weakly bound ligands: SO 2 , halogenated acetonitriles and nitromethane with comprehensive characterization including structural, magnetic and spectral (IR) properties as well as thermal stability assessment. The use of these simple yet rarely encountered ligands yields mostly stable and highly Lewis-acidic com-plexes, in some cases comparable to SbF 5 according to calculated Fluoride Ion Affinities. Highly acidic character of the species is also reflected in observed reactivity. Since the most convenient route towards the Co(II) complexes leads through silver salts, the results are complemented with characterization of a series of novel Ag(I) complexes with abovementioned ligands. Experimental part is backed with DFT calculations which gives insight into the structure and energetics of presented Co(II) complexes and shows that Co(II) center is available for substrates like olefins. This makes them good candidates for catalysts in reactions requiring the presence of Lewis acids.