New Form of Aluminum Unlocks Cheaper and More Sustainable Catalysts

Dr Clare Bakewell, Senior Lecturer in the Department of Chemistry at King’s College London, is leading research that may shift how chemists think about catalyst design. In work published in Nature Communications, Bakewell and her team report the isolation of a neutral cyclic aluminum(I) trimer, a molecular structure that expands the known chemistry of aluminum and opens discussion about replacing precious metals in certain catalytic processes.

Squire, I., de Vere-Tucker, M., Tritto, M., Silva de Moraes, L., Krämer, T., & Bakewell, C. (2026). A neutral cyclic aluminium (I) trimer. Nature Communications, 17(1), 1732. https://doi.org/10.1038/s41467-026-68432-1

Catalysis sits at the center of modern chemical manufacturing. From polymer production to fuel processing and pharmaceutical synthesis, catalysts enable reactions to proceed efficiently and selectively. Many of the most established systems rely on transition metals such as platinum, palladium and rhodium. These metals are effective but costly, and their supply chains are vulnerable to geopolitical and environmental pressures. As industries look to reduce dependence on rare and precious metals, chemists have increasingly turned to more abundant elements.

Dr Clare Bakewell, Senior Lecturer in the Department of Chemistry at King’s College London stated,

“Chemists have been looking towards more common elements from the periodic table, and we chose aluminum, as it’s super abundant, making it ~20,000 times less expensive than precious metals such as platinum and palladium.”

Aluminum stands out because of its abundance and global availability. It is widely used in structural alloys and packaging, yet in molecular chemistry it has traditionally been associated with higher oxidation states and relatively limited reactivity compared to transition metals. The King’s College London study challenges that perception by stabilizing aluminum in the +1 oxidation state within a discrete cyclic trimer.

The compound consists of three aluminum atoms arranged in a triangular configuration. This neutral cyclic aluminum(I) trimer, sometimes described as a cyclotrialumane, represents the first example of its kind isolated in a neutral form. Structural characterization confirmed that the triangular framework persists in solution rather than fragmenting or rearranging. That persistence is significant because many low oxidation state main group compounds are highly sensitive and lose structural integrity outside of solid state conditions.

Maintaining structural integrity in solution is essential if a compound is to participate in catalytic cycles. In catalysis, the active species must repeatedly bind substrates, transform them and release products without decomposing. The stability of the aluminum trimer under solution conditions suggests that it could serve as a platform for further reactivity studies.

Laboratory investigations showed that the trimer is capable of cleaving dihydrogen, a reaction commonly associated with transition metal complexes. The activation of the hydrogen hydrogen bond is often considered a benchmark for catalytic competence. Demonstrating this type of reactivity with an earth abundant main group element broadens the conceptual framework for catalyst development.

The team also explored reactions with ethene, a fundamental feedstock in the chemical industry and the basis for polyethylene production. The aluminum trimer engages in stepwise insertion reactions with ethene, leading to the formation of five membered and seven membered aluminum carbon rings. These ring forming processes reveal that the compound does more than activate small molecules. It participates in bond construction pathways that could, in principle, be extended to more complex transformations.

The broader context of this work lies in the ongoing effort to expand main group chemistry into areas traditionally dominated by transition metals. Over the past decade, chemists have shown that elements such as boron, silicon and aluminum can exhibit reactivity once thought exclusive to d block metals. These discoveries often require careful ligand design to stabilize unusual oxidation states while preserving reactive capacity. The neutral aluminum(I) trimer reported by Bakewell’s group contributes to this evolving landscape by demonstrating that a cyclic arrangement of aluminum atoms can balance stability and reactivity.

Economic considerations reinforce the scientific interest. Aluminum is among the most abundant metals in the Earth’s crust and is produced at large industrial scale. In contrast, platinum group metals are relatively scarce and geographically concentrated. While molecular aluminum complexes are not interchangeable with bulk aluminum metal, the accessibility of the element provides a foundation for potentially more secure and cost effective catalyst systems.

The research also sheds light on how aluminum atoms interact when removed from their typical oxide or metallic environments. The triangular arrangement in the trimer reflects a unique bonding situation that challenges textbook descriptions of aluminum chemistry. Understanding these bonding patterns is not purely academic. Electronic structure and atomic arrangement determine how substrates approach and bind to reactive centers. By mapping these interactions, chemists can design more efficient catalytic systems.

At this stage, the work remains exploratory. The reported reactions were conducted under controlled laboratory conditions using purified substrates. Further studies will be required to evaluate catalytic turnover numbers, long term stability and compatibility with functionalized molecules. Translating a molecular discovery into an industrial catalyst requires extensive testing, optimization and economic assessment.

Nevertheless, the discovery provides a foundation for rethinking the role of main group metals in chemical synthesis. If aluminum based systems can be tuned to achieve competitive performance, they may reduce reliance on metals that are costly to mine and refine. The environmental footprint associated with extracting and processing precious metals is substantial. Substituting part of that demand with catalysts derived from more abundant elements could contribute to more sustainable production pathways.

The work from King’s College London aligns with broader trends in sustainable chemistry. Researchers worldwide are exploring ways to redesign catalytic processes to lower energy inputs, reduce waste and rely on readily available materials. Advances in spectroscopy, computational chemistry and synthetic methodology have enabled the stabilization of species that were once considered too reactive to isolate. The neutral aluminum(I) trimer is one such example.

Dr Bakewell has emphasized that the field is still in its early stages. The chemistry revealed so far suggests capabilities that extend beyond simply mimicking transition metals. The formation of new ring systems and the retention of a defined cyclic structure during reaction hint at reactivity patterns that could diverge from established catalytic paradigms. Such divergence is often where meaningful innovation occurs.

For chemical engineers and industrial chemists, the significance of the work lies not in immediate replacement of existing catalysts but in expanding the design space. Each new class of reactive compound introduces additional variables for process optimization. Over time, incremental improvements accumulate and can reshape entire sectors of chemical manufacturing.

In summary, the isolation of a neutral cyclic aluminum(I) trimer by Dr Clare Bakewell and her colleagues represents both a structural milestone and a conceptual advance. It demonstrates that aluminum, long valued for its abundance and structural uses, can also participate in sophisticated bond activation chemistry. Whether this leads directly to commercial catalysts or informs the next generation of main group systems, it contributes to a broader shift toward more accessible and potentially more sustainable catalytic materials.