Exploring Equilibria between Aluminium(I) and Aluminium(III): The Formation of Dihydroalanes, Masked Dialumenes and Aluminium(I) Species

TY - JOUR

T1 - Exploring Equilibria between Aluminium(I) and Aluminium(III)

T2 - The Formation of Dihydroalanes, Masked Dialumenes and Aluminium(I) Species

AU - Bakewell, Clare

AU - Hobson, Katie

AU - Carmalt, Claire J.

N1 - Funding Information: The Ramsay Memorial trust (C.B.) are thanked for their financial support and UCL Chemistry are thanked for providing a departmental studentship (K.H.). Dr. Abil Aliev is thanked for his assistance running VT NMR experiments. Publisher Copyright: © 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.

PY - 2022/8/1

Y1 - 2022/8/1

N2 - The design of new reductive routes to low oxidation state aluminium (Al) compounds offers the opportunity to better understand redox processes at the metal centre and develop reactivity accordingly. Here, a monomeric AlI compound acts as a stoichiometric reducing agent towards a series of AlIII dihydrides, leading to the formation of new low oxidation state species including symmetric and asymmetric dihydrodialanes, and a masked dialumene. These compounds are formed by a series of equilibrium processes involving AlI, AlII and AlIII species and product formation can be manipulated by fine-tuning the reaction conditions. The transient formation of monomeric AlI compounds is proposed: this is shown to be energetically viable by computational (DFT) investigations and reactivity studies show support for the formation of AlI species. Importantly, despite the potential for the equilibrium mixtures to lead to ill-defined reactivity, controlled reactivity of these low oxidation state species is observed.

AB - The design of new reductive routes to low oxidation state aluminium (Al) compounds offers the opportunity to better understand redox processes at the metal centre and develop reactivity accordingly. Here, a monomeric AlI compound acts as a stoichiometric reducing agent towards a series of AlIII dihydrides, leading to the formation of new low oxidation state species including symmetric and asymmetric dihydrodialanes, and a masked dialumene. These compounds are formed by a series of equilibrium processes involving AlI, AlII and AlIII species and product formation can be manipulated by fine-tuning the reaction conditions. The transient formation of monomeric AlI compounds is proposed: this is shown to be energetically viable by computational (DFT) investigations and reactivity studies show support for the formation of AlI species. Importantly, despite the potential for the equilibrium mixtures to lead to ill-defined reactivity, controlled reactivity of these low oxidation state species is observed.

KW - Aluminium

KW - Low Oxidation State

KW - Masked Dialumene

KW - Redox

KW - Reversible

UR - http://www.scopus.com/inward/record.url?scp=85130452974&partnerID=8YFLogxK

U2 - 10.1002/anie.202205901

DO - 10.1002/anie.202205901

M3 - Article

AN - SCOPUS:85130452974

SN - 1433-7851

VL - 61

JO - Angewandte Chemie - International Edition

JF - Angewandte Chemie - International Edition

IS - 31

M1 - e202205901

ER -