Dramatic structural changes of donor-functionalized alkoxides of aluminium upon replacement of the ester functionality by ketone

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Janusz Lewiński, Iwona Justyniak, Zbigniew Ochal and Janusz Zachara


Abstract

Upon replacement of the ester functionality by ketone functionality in α-hydroxy carbonyl compounds dramatic structural changes of donor-functionalized alkoxides of aluminium are observed: complete reversal of the stereochemistry of the aluminium alkoxide adduct formation, dissociation of the five-coordinate dimer to a monomeric four-coordinate chelate complex; the first example of an aluminium Cram-type chelate complex derived from the reaction of Et3Al with an equimolar amount of rac-acetoin is reported.


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