Boosting Low-Valent Aluminum(I) Reactivity with a Potassium Reagent

Grams S, Eyselein J, Langer J, Färber C, Harder S (2020)

Publication Type: Journal article

Publication year: 2020

Journal

DOI: 10.1002/anie.202006693

Abstract

The reagent RK [R=CH(SiMe3)2 or N(SiMe3)2] was expected to react with the low-valent (^DIPPBDI)Al (^DIPPBDI=HC[C(Me)N(DIPP)]2, DIPP=2,6-iPr-phenyl) to give [(^DIPPBDI)AlR]⁻K⁺. However, deprotonation of the Me group in the ligand backbone was observed and [H2C=C(N-DIPP)−C(H)=C(Me)−N−DIPP]Al⁻K⁺ (1) crystallized as a bright-yellow product (73 %). Like most anionic Al^I complexes, 1 forms a dimer in which formally negatively charged Al centers are bridged by K⁺ ions, showing strong K⁺⋅⋅⋅DIPP interactions. The rather short Al–K bonds [3.499(1)–3.588(1) Å] indicate tight bonding of the dimer. According to DOSY NMR analysis, 1 is dimeric in C6H6 and monomeric in THF, but slowly reacts with both solvents. In reaction with C6H6, two C−H bond activations are observed and a product with a para-phenylene moiety was exclusively isolated. DFT calculations confirm that the Al center in 1 is more reactive than that in (^DIPPBDI)Al. Calculations show that both Al^I and K⁺ work in concert and determines the reactivity of 1.

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How to cite

APA:

Grams, S., Eyselein, J., Langer, J., Färber, C., & Harder, S. (2020). Boosting Low-Valent Aluminum(I) Reactivity with a Potassium Reagent. Angewandte Chemie International Edition. https://dx.doi.org/10.1002/anie.202006693

MLA:

Grams, Samuel, et al. "Boosting Low-Valent Aluminum(I) Reactivity with a Potassium Reagent." Angewandte Chemie International Edition (2020).

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