Tandem reactions catalyzed by lanthanide iodides. Part 1: Tandem Mukaiyama-Michael iminoaldol reactions

Samarium diiodide, as well as lanthanide triiodides catalyze a one-pot procedure allowing to perform sequentially the Mukaiyama-Michael addition of a ketene silyl acetal on a cyclic α,β-unsaturated ketone, followed by the addition of a glyoxylic, aromatic or heteroaromatic imine. According to the nature of the silyl group the adducts resulting from this tandem process are isolated as ketones or as enoxysilanes. The presence of a coordinating group on the imine increases the rate of the reaction.