Oxygen Heterocycles by Sulphur Ylide Annulation: Synthesis of 3,4-Dihydro-2H,5H-pyrano[3,2-c][1]benzopyran-5-ones by Dimethylsulphoxonium Methylide

Abstract
3,4-Dihydro-2-hydroxymethyl-2H,5H-pyrano[3,2-c][1]benzopyran-5-ones are the main products of the reaction of dimethylsulphoxonium methylide on Michael adducts of 4-hydroxycoumarins and α,β-unsaturated ketones. Minor quantities of 3,4-dihydro-2-hydroxymethyl-2H,5H-pyrano[2,3-b][1]benzopyran-5-ones are also sometimes obtained

This publication has 0 references indexed in Scilit: