Treatment of diazo vinyl phosphonate
with alcohols, amines, and
thiols in the presence of Rh­(II) results in the chemo- and stereoselective
generation of enol ethers, enamines and vinyl sulfides via an X–H
insertion process. The utility of the products from these reactions
was demonstrated through their conversion into quaternary substituted
heterocycles including furans and oxetanes as highlighted by the generation
of a bicyclic phosphonate analogue of neodysiherbaine