Synthesis and spectroscopic studies of alkylaluminum alkoxides derived from optically active alcohols. Crystal and molecular structure of monomeric dimethylaluminum (2S,3R)-(+)-4-(dimethylamino)-1,2-diphenyl-3-methyl-2-butanoxide

Structural diversity and versatility for organoaluminum complexes supported by mono- and di-anionic aminophenolate bidentate ligands

“…The six-membered-ring Al metallacycle is significantly puckered with the Al-NH(Diip) moiety well above the nearly planar C(15)eC(6)eO (1)eAl (1) backbone, as shown by the O(1)eC (1)eC(15)eN(1) and C(15)eC(6)eAl (1)eO (1) torsion angles (54.73 and 50.57 , respectively), thus resulting in an overall C 1 symmetry for compound 5d in the solid state. The AleO and AleN bond distances (1.768 (2) and 2.049(2) Å, respectively) are in the normal range found for aluminium phenolates (1.640(5)-1.773(2) Å) [14] and for AleN dative bonds (1.957(3)-2.238(4) Å) [15], respectively. As for the behaviour of compound 5d in the (1), 1.7816(19); Al(2)eN(2), 1.7759 (19); Al (2)eO (1), 1.8402(14); Al(2)eO(2), 1.8463 (15); Al(1)eO(1), 1.8591 (15); Al(1)eO(2), 1.8678 (15); Al(1)eC (1) solution, all NMR data agree with the effective chelation of the LX À -type {2-CH 2 NH(Diip)-4,6-t Bu 2 -C 6 H 2 O} À anion onto Al along with an overall C 1 symmetry.…”

“…The AleO and AleN bond distances (1.768 (2) and 2.049(2) Å, respectively) are in the normal range found for aluminium phenolates (1.640(5)-1.773(2) Å) [14] and for AleN dative bonds (1.957(3)-2.238(4) Å) [15], respectively. As for the behaviour of compound 5d in the (1), 1.7816(19); Al(2)eN(2), 1.7759 (19); Al (2)eO (1), 1.8402(14); Al(2)eO(2), 1.8463 (15); Al(1)eO(1), 1.8591 (15); Al(1)eO(2), 1.8678 (15); Al(1)eC (1) solution, all NMR data agree with the effective chelation of the LX À -type {2-CH 2 NH(Diip)-4,6-t Bu 2 -C 6 H 2 O} À anion onto Al along with an overall C 1 symmetry. For instance, the 1 H NMR spectrum contains two Al-Me singlet resonances (d À0.49 and À0.18), two sets of signals for the PhCHH' groups (d 3.31 and 4.75) and a doublet resonance (d 5.18, 3 J HH ¼ 11Hz) assigned to the NH entity.…”

Synthesis and Structures of Aminoalkoxyalanes

“…Thus, the Me 2 Al and the Me 2 Ga derivatives of the darvon alcohol [(ϩ)-(2S,3R)-4-dimethylamino-1,2-diphenyl-2-butanol] are monomeric in the solid state. [10] Interestingly, reactions of R 2 AlCl (R ϭ Me, Et) with amino alcohols not only gives access to dimeric aminoalkoxy alkyl chloroalanes [R*OAl(R)Cl] 2 but, in the case of Me 2 AlCl and (S)-α,α-diphenyl-2-pyrrolidinyl methanol, an ionic complex {MeAl(R*O) 2 AlMe] ϩ [MeAlCl 3 ] Ϫ is formed. [12] Although compounds 1؊5 are the first structurally characterized aminoalkoxyalanes, one gallium homologue has been reported previously: N,NЈЈ-dimethylaminoethoxydihydridogallane.…”

Darstellung, Eigenschaften und Molekülstrukturen von chiralen Dimethylaluminium-aminoalkoxiden

“…(1) zu den Dimethylaluminiumalkoxiden 1±4. [7], was auch bei analogen Me 2 GaOR*-Verbindungen der Fall ist [8]. Das im Vergleich zu den Verbindungen 1±3 nach tieferem Feld verschobene entsprechende Signal von 4 bei ±0,25 ppm ist mo È glicherweise auf die Wirkung der am N-Atom gebundenen elektronegativen Benzylgruppe zuru È ckzufu È hren.…”

“…Im Jahre 1992 wurde von Oliver et al die Synthese von Dialkylaluminiumalkoxiden mit chiralen C-Atomen in den Alkoxidresten beschrieben, wobei die urspru È ngliche optische Aktivita È t der eingesetzten Alkohole bei der Bildung der Alkoxide erhalten bleibt [6]. Bei weiteren Verbindungen dieser Art wurden 2-N-Methylpyrrolidyl-methoxid-Reste mit dem Al-Atom verknu È pft [7]. Die Autoren diskutierten in den erhaltenen Verbindungen die Ausbildung zusa È tzlicher Chelatringe als Folge einer Al±N-Wechselwirkung.…”