Unravelling White Phosphorus: Experimental and Computational Studies Reveal the Mechanisms of P4 Hydrostannylation

The hydrostannylation of white phosphorus (P 4 ) allows this crucial industrial precursor to be easily transformed into useful P 1 products via direct, ‘one pot’ (or even catalytic) procedures. However, a thorough mechanistic understanding of this transformation has remained elusive, hindering attempts to use this rare example of successful, direct P 4 functionalization as a model for further reaction development. Here, we provide a deep and generalizable mechanistic picture for P 4 hydrostannylation by combining DFT calculations with in situ 31 P NMR reaction monitoring and kinetic trapping of previously unobservable reaction intermediates using bulky tin hydrides. The results offer important insights into both how this reaction proceeds and why it is successful and provide implicit guidelines for future research in the field of P 4 activation.