Harnessing Potent Reductants via Multiphoton Tandem Photoredox Catalysis

Wednesday, 26 April 11:00am – 12:00pm

This seminar will be delivered in Chemistry Lecture Theatre 4 and Online Zoom Please email chemistry.researchsupport@sydney.edu.au for zoom link and password.

Speaker: Dr Anastasios Polyzos, University of Melbourne

Host: Prof. RIch Payne

Title: Harnessing Potent Reductants via Multiphoton Tandem Photoredox Catalysis

Abstract:

The renaissance of photoredox catalysis has invigorated the discovery of new reactivity in synthetic chemistry. Despite advances in the field, the development of photoredox catalysed methods that engage inert organic substrates in single electron transfer (SET) mediated transformations, generally remains beyond the scope of contemporary catalyst design. To address this challenge, we have recently reported a tandem catalytic cycle of [Ir(ppy)₂(dtb-bpy)]⁺, which generates a highly reducing iridium analogue (Ir2*) in situ via a multiphoton promoted second catalytic cycle¹. This tandem catalytic strategy unlocks the reactivity of energy demanding substrates including organohalides², olefins³ and imines with a single, readily available, photocatalyst with mild reaction conditions, and exceptional functional group tolerance. The discovery and application of this platform to the development of strategic organic transformation in batch, and flow will be discussed.

1. Am. Chem. Soc. 2019 141, 17646–17658.
2. Chem. Int. Ed. 2020 132, 2-11.
3. ACS Catal. 2021 9, 5472–5480.

Bio:

Dr Anastasios (Tash) Polyzos is a Senior Lecturer and ARC Future Fellow at the University of Melbourne. Tash completed his doctoral studies in 2005 at La Trobe University and appointed to Research Fellow at the Australian National research agency, CSIRO in the same year. In 2008 he pursued post-doctoral research at University of Cambridge under guidance of Professor Steven V. Ley FRS. In 2011 he returned to Australia and lead the flow chemistry and catalysis group at CSIRO in Australia. He then embarked on an independent career in 2015 when he was appointed to the University of Melbourne.

His group’s accomplishments have been recognised by several achievements including the 2021 Grimwade Prize for Industrial Chemistry, Max O’Conner Award and Lectureship (2018), La Trobe University (2018) the Thieme Chemistry Journals Award (2017), Visiting Professorship, ETH Zurich (Swiss Federal Institute of Technology) (2016) and the Julius Career Award, CSIRO, Australia (2013).

His research interests include the development of new methods and enabling technologies for organic synthesis, photocatalysis, C-H reaction discovery, and the development of sustainable industrial process chemistry. He currently serves as Director of the Australian Research Council Industrial Transformation Training Centre for Chemical Industries.