1,4-Dioxobenzene compounds of aluminium

Abstract

The aluminium aryloxide polymer, [{(^tBu)₂Al}₂(μ-OC₆H₄O)]_n (1) is synthesized by the addition of Al(^tBu)₃ to hydroquinone in a non-coordinating solvent, and reacts with Lewis bases, via both a solution and a solid/vapor reaction, to yield [(^tBu)₂Al(L)]₂(μ-OC₆H₄O) [L = py (2), 3,5-Me₂py (3) and THF (4)] via cleavage of the Al₂O₂ dimeric core. Thermolysis of 2–4 results in decomposition without clean formation of compound 1. However, if compound 2 is formed by the exposure of 1 to pyridine vapors, subsequent thermolysis allows for the clean solid state interconversion of compounds 1 and 2. The room temperature solid state reaction of [{(^tBu)₂Al}₂(μ-OC₆H₄O)]_n (1) with pyrazine (pz), 4,4′-bipyridine (4,4′-bipy) or 1,4-benzoquinone (1,4-bz) results in a rapid color change and the formation of [{(^tBu)₂Al}₂(μ-OC₆H₄O)(μ-L)]_n, where L = pz (5), 4,4′-bipy (6) and 1,4-bz (7).