Here, we report on a methodology for the C-allylation of α-ketophosphonates 2 via a [3,3]-sigmatropic shift of the corresponding allylenolphosphonates, 3 (Scheme 3). Furthermore, we will show that asymmetric α-ketophosphonates undergo this reaction with diastereoselectivity and that the selectivity in these reactions is influenced by chirality at the phosphorus. ... When heated at reflux in toluene, phosphoenols 5a−7a and 5b−7b underwent a clean and facile [3,3]-sigmatropic ...
