Iodotrimethylsilane induced diastereoselective synthesis of tetrahydropyranones by a tandem Knoevenagel–Michael reaction

The synthesis of multifunctionalized tetrahydropyranones has been achieved at room temperature with iodotrimethylsilane by a tandem Knoevenagel condensation of aldehydes with aldol adducts prepared from β-keto esters and aldehydes, followed by a Michael reaction. The reactions are highly diastereoselective affording a single isomer in high yields.