Cationic Aluminium Complexes as Catalysts for Imine Hydrogenation.

ABSTRACT: Strongly Lewis acidic cationic aluminium complexes, stabilized by β-diketiminate (BDI) ligands and free of Lewis bases, have been prepared as their B(C₆ F₅ )₄ ^- salts and were investigated for catalytic activity in imine hydrogenation. The backbone (R1) and N (R2) substituents on the ^R1,R2 BDI ligand (^R1,R2 BDI=HC[C(R1)N(R2)]₂ ) influence sterics and Lewis acidity. Ligand bulk increases along the row ^Me,DIPP BDI<^Me,DIPeP BDI≈^tBu,DIPP BDI<^tBu,DIPeP BDI; DIPP=2,6-C(H)Me₂ -phenyl, DIPeP=2,6-C(H)Et₂ -phenyl. The Gutmann-Beckett test showed acceptor numbers of: (^tBu,DIPP BDI)AlMe⁺ 85.6, (^tBu,DIPeP BDI)AlMe⁺ 85.

SUBMITTER: Friedrich A 

PROVIDER: S-EPMC8252007 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature