Monday, 15 March 4:00pm – 4:45pm

This seminar will be delivered via Zoom – Please email chemistry.researchsupport@sydney.edu.au for zoom link and password.

Speaker: Dr Jamie Hicks; Australian National University

Host: Dr Jonathan Danon

Title: Nucleophilic aluminium: Synthesis, structural and reaction chemistry of the aluminyl anion

Biography:

Jamie Hicks obtained his Ph.D. from Monash University, Melbourne (2012-2015) under the supervision of Prof. Cameron Jones. He worked on the synthesis and reactivity of low-coordinate, low-oxidation state transition metal complexes for which he won a number of awards, including the Springer Thesis prize (2016) and the 2016 Reaxys PhD Prize. He then undertook a postdoctoral position at the same institution under the joint supervision of Prof. Stuart Batten and Dr. David Turner (2015-2016), working on the incorporation of amines into porous coordination polymers. Jamie then moved to the UK to undertake his second postdoctoral appointment at the University of Oxford (2016-2019), under the joint supervision of Profs Jose Goicoechea and Simon Aldridge, working on the synthesis and reactivity of nucleophilic aluminium complexes. Jamie has recently been awarded an ARC Discovery Early Career Researcher Award (DECRA), which he started in June 2019 at the Australian National University, Canberra. His current work involves the synthesis of highly reactive heterobimetallic complexes for N₂ activation.

Abstract:

Aluminium is the most abundant metal in the Earth’s crust and is widely exploited in a number of key industrial processes. Being located in group 13 of the Periodic Table, it possesses four valence orbitals but only three valence electrons. Its reactivity is therefore dominated by its electron deficiency and electropositivity: Al(III) compounds are archetypal electrophiles. Last year, we reported that anionic Al(I) compounds can act as nucleophiles, with the dimethylxanthene-stabilized potassium aluminyl compound [K{(NON)Al}]₂.^[1] The complex has been shown to react in an unprecedented ‘umpolung’ fashion as an aluminium-centred nucleophile in the formation of a range of Al-E covalent bonds (E = H, C or metals), including in the synthesis of the first nucleophilic gold compound [(NON)AlAuP^tBu₃].^[2]

More recently, it has been found the potassium aluminyl and the related monormeric complex [K(2.2.2-crypt)][(NON)Al] show fascinating reactivity towards a range of small molecules, including simple arenes.  Once such example is that the monomeric species was found to insert into the C-C bond of benzene to give the 7-membered heterocycle [K(2.2.2-crypt)][(NON)AlC₆H₆] (Figure 1).^[3]  This C-C bond activation of benzene was found to be reversible; mechanistic details and functionalisation of the C-C bond activation will be discussed.

Figure 1.  C-C bond activation of benzene by a monomeric aluminyl complex.

References

[1] J. Hicks, P. Vasko, J. M. Goicoechea, S. Aldridge, Nature, 2018, 557, 92–95.

[2] J. Hicks, A. Mansikkamäki, P. Vasko, J. M. Goicoechea, S. Aldridge, Nature Chemistry, 2019, 11, 237–241.

[3] J. Hicks, P. Vasko, J. M. Goicoechea, S. Aldridge, J. Am. Chem. Soc. 2019, 141, 11000–11003.