# Reactivity of Diaryl Bismuth Cations toward a Platinum(0) Complex: Oxidative Aryl Transfer

## TL;DR

This paper studies how diaryl bismuth cations react with a platinum complex, revealing a new oxidative aryl transfer process.

## Contribution

The study reports an unprecedented bismuth-to-platinum oxidative aryl transfer reaction and the formation of PtII complexes.

## Key findings

- Isolable metal-only Lewis pairs were not formed, unlike with the methyl analogue.
- Oxidative aryl transfer produced PtII complexes [PtAr(PCy3)2(SbF6)].
- Attempts to trap intermediates led to a PtII semiquinone radical complex.

## Abstract

Reactions of three aryl-substituted bismuth cations,
[BiPh2(SbF6)], [BiMes2(SbF6)],
and [BiDipp2(SbF6)], with the Pt0 complex Pt­(PCy3)2 have been investigated (Mes
= 2,4,6-trimethyl-phenyl; Dipp = 2,6-di-iso-propyl-phenyl;
Cy = cyclohexyl). Unexpectedly, and in contrast with the reactivity
of the recently reported methyl analogue [BiMe2(SbF6)], the formation of isolable metal-only Lewis pairs [(Cy3P)2Pt→BiAr2(SbF6)]
is not observed (Ar = aryl). Instead, an unprecedented bismuth-to-platinum
oxidative aryl transfer is witnessed to give the PtII complexes
[PtAr­(PCy3)2(SbF6)], along with the
suggested bismuthinidene intermediates BiAr. Attempts to trap these
fleeting intermediates with an ortho-quinone led
to a PtII semiquinone radical complex.