Structure, Bonding, and Reactivity of Organoaluminum Molecular Species: A Computational Perspective

Abstract

This chapter describes the theoretical studies of organoluminum molecules involving one or more aluminum centers, as well aluminum hydride and halide. Selected systems containing other Group 13 elements are also included when they contribute to the understanding of organoaluminum systems. This review includes small to large molecular systems and mono to polyaluminum species that have been studied by a wide variety of methods from molecular orbital analysis and semiempirical methods to the most elaborate wave‐function correlated methods. The electronic structures are presented, and the structure–electronic structure relationships are discussed. The calculations illustrate how the oxidation states and the coordination number influence the structural and electronic properties of the complexes. The Lewis acid character of Al III , the polarity of the Al(δ+)–C(δ−) bond, and the rarity of the multiple bond to Al appear as the leading factors. Carbon monoxide, alkyl, alkene, alkyne, aryl, cyclopentadienyl, and arene complexes of aluminum are described in detail. The polyaluminum species include systems with direct Al–Al interaction or interaction by way of bridging groups. The structures and role of methyl aluminum oxides (MAO) on polymerization are presented. The chapter ends with the description of mechanisms for reactions of selected organoaluminum reagents derived from computational studies.

Ene/Diene Copolymerization Catalyzed by Cationic Sc and Gd d0 Metal Complexes: Speciation, Ion Pairing, and Selectivity from a Computational Perspective

“…Optimization attempts of clusters with a higher degree of aggregation turned out to be dissociative. This is in line, so far, with the absence of characterization of larger aggregates , and the bonding picture of alkylaluminum compounds …”

“…This is in line, so far, with the absence of characterization of larger aggregates 44,45 and the bonding picture of alkylaluminum compounds. 46 Determination of Dormant and Active Species. Though the cationic mono-indenyl species Sc 2 and Sc 4 (Schemes S1 and S6) were synthesized and characterized by X-ray diffraction analysis, we have also considered a pathway in which the cationic bis(indenyl) species Sc 3 is formed resulting from the abstraction of the amido group by the trityl cation (Schemes S1 and S6).…”

Synthesis and biological activities of organoaluminum steroids

“…[3] Organoaluminum chemistry is part of the organometallic chemistry that studies the compounds of aluminum and carbon, as well as their chemical bonds (C-Al). [4][5][6] A large number of articles devoted to the study of organic compounds of aluminum have been published in the past almost two hundred years, the citation of which is not possible. However, it should be noted that the last 10 years have been published two monographs, which are devoted exclusively to the chemistry of organoaluminum compounds, and include the citation of previous publications.…”