Preparation of functionalized organoaluminiums by direct insertion of aluminium to unsaturated halid

Abstract

The preparation of polyfunctional organometallics is important in organic synthesis as these reagents are very popular nucleophiles. The preparation of functionalized aluminium reagents by direct insertion of aluminium powder is in general not possible. Such a reaction would be of special importance owing to the low price of aluminium compared with magnesium (it is half the price), the low toxicity of this metal and the chemoselectivity of the resultant organoaluminium reagents. We have now found that by adding catalytic amounts of selected metallic chlorides (TiCl4, BiCl3, InCl3 or PbCl2) in the presence of LiCl, aluminium powder inserts into various unsaturated iodides and bromides under mild conditions. These resulting new organoaluminium reagents undergo smooth Pd-catalysed cross-coupling and acylation reactions, as well as copper-catalysed allylic substitutions, affording various interesting products for pharmaceutical and material science applications. The reactivity of organoaluminium reagents makes them particularly attractive nucleophiles for a wide range of organic reactions. Here, the use of metal halide catalysts provides access to functionalized organoaluminium reagents directly from the metal. The utility of these organoaluminium reagents is then demonstrated by their reaction with a wide variety of electrophilic coupling partners.

Cite this article

Blümke, T., Chen, YH., Peng, Z. et al. Preparation of functionalized organoaluminiums by direct insertion of aluminium to unsaturated halides. Nature Chem 2, 313–318 (2010). https://doi.org/10.1038/nchem.590

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