Postgraduate Scholarship in Main Group Chemistry - Phosphenium Cations: Phospha-Friedel-Crafts Intermediates for Modern Synthesis

This project aims to reassess the fundamental nature and reactivity of phosphenium cations. Phospha-Friedel-Crafts chemistry (with unstabilised cationic phosphenium intermediates) for the formation of carbon-phosphorous bonds has been known for over a century but is barely used due to the harsh conditions required and poor reaction control. Our recent isolation of a weakly stabilised phosphenium cation and subsequent studies of its reactivity challenge the accepted wisdom on the nature and extent of stabilisation in these systems. To date phosphenium cations have been regarded as curiosities as a result of their extreme Lewis acidity. Conceptually however these systems could be employed in any reaction system that utilises Lewis acids. This project will focus on isolating and characterising phosphenium cation adducts, studying their fundamental properties and ultimately utilising these adducts for new synthetic chemistries, as main group catalysts and bespoke, stoichiometric reagents for novel transformations.

The project will involve main group and organic synthesis and the solid and solution state characterisation of new systems, primarily using multinuclear NMR, single crystal XRD, and cyclic voltammetry, backed up by DFT calculations.

The successful candidate will be based at the University of Kent’s main campus in Canterbury under the supervision of Dr Ewan Clark, as part of the Functional Materials Group of the School of Physical Sciences.

This PhD Studentship is due to start in September 2018.