Alkali metal influences in aluminyl complexes

Abstract

The previously reported K aluminyl complex [(BDI-H)AlˉK+]2 was converted in Li+ or Na+ salts by a salt metathesis reaction with Li(BPh4) or Na(BPh4), respectively; BDI-H = dianionic [(DIPP)N-C(Me)=C(H)-C(=CH2)-N(DIPP)2ˉ] and DIPP...

Synthesis, Characterization, and Structural Analysis of AM[Al(NONDipp)(H)(SiH2Ph)] (AM = Li, Na, K, Rb, Cs) Compounds, Made Via Oxidative Addition of Phenylsilane to Alkali Metal Aluminyls

“…Harder and co-workers have recently expanded the series of aluminyls containing the [Al­(BDI-H)] − ([BDI-H] 2– = [DippNC­(Me)C­(H)­C­(CH 2 )­NDipp] 2– ; D Figure ) anion to encompass the full series [ AM {Al­(BDI-H)}] 2 ( AM = Li–Cs) . Analogous to our results, the lithium and sodium derivatives have been isolated as the slipped CDPs and can be easily converted into the corresponding monomeric ion pairs (MIPs), (BDI-H)­Al–Li­(Et 2 O) 2 , and (BDI-H)­Al–Na­(Et 2 O) (TMEDA), when exposed to coordinating solvents.…”

“…The relative dimerization energies calculated for 2 AM [Al(BDI-H)] → [ AM {Al(BDI-H)}] 2 show a regular decrease as the size of the alkali metal increases. 18 However, when the opposing solvation effects [polarizable continuum model (PCM) = benzene, which favor the monomer due to solvent–metal interactions] and dispersion effects (which favor the dimer through attractive interactions between ligands) are incorporated in the calculations, the trend is less well defined with, for example, the Δ G value for AM = Na (−21.1 kcal mol –1 ) less than that for AM = K (−25.4 kcal mol –1 ). We have noted a similar trend with the 2 AM [Al(NON Dipp )] → [ AM {Al(NON Dipp )}] 2 system, 17 wherein PCM = toluene with a Δ G value for AM = Na (−26.7 kcal mol –1 ) less than that for AM = K (−33.6 kcal mol –1 ).…”

The emerging chemistry of the aluminyl anion

“…Diffusion ordered spectroscopy (DOSY) NMR experiments on these systems are consistent with retention of these associated dimeric structure in solution. In addition, the CDP motif has now been structurally verified for the series of [AM{Al(NON)}] 2 (AM = Li 7, Na 8, Rb 13 and Cs 14), 38,42 and the [BDI Dipp 38,40,41 DFT calculations show that a single Al-AM bond exists within these 'slipped' CDPs, in contrast with the heavier congeners (AM = K, Rb, Cs) that form 'symmetric' or 'twisted' dimers with the Al atoms engaging in contacts to both AM cations (vide infra).…”

“…31 This work has recently been complimented by the demonstrated interconversion of 9 2 19, 40 11 2 17 and 12 2 18. 41 2.4.3 Separated ion pairs (SIPs). A third structure type for the aluminyls was noted in the initially synthesized potassium (alkyl)(amido) aluminyl 5.…”

Al–Sc Bonded Complexes: Synthesis, Structure, and Reaction with Benzene in the Presence of Alkyl Halide

“…Mixing copper chloride with a newly prepared neutral Al­(I) species led to the formation of Al–Cu complex E through oxidative addition of Cu–Cl bond to the Al­(I) center (Figure c) . Inspired by the transmetalation reactions of the recently developed Al anions with group 1, 2, and 12 metal salts, ,, reactions of Al anions with TM-halides were also demonstrated to afford Al–TM complexes F and G possessing a three-coordinate X-type Al ligand (Figure c). , It should be noted that G is the sole example of early transition metal–Al complex with an X-type Al ligand, although compounds possessing a dative Al-lanthanide or actinide bond have been reported . However, the reactivity of early-metal–Al complexes has not been reported.…”