Synthesis of Coumestrol and Aureol

A total synthesis of coumestrol (<b>1</b>) and aureol (<b>2</b>) is described. The Perkin condensation of 2-bromo-4-hydroxylphenylacetic acid (<b>6</b>) and <i>o</i>-hydroxybenzaldehydes (<b>7</b>) gave the corresponding 2′-bromo-3-arylcoumarins (<b>9</b>). A copper-catalyzed consecutive hydroxylation and aerobic oxidative coupling of <b>9</b> under microwave conditions facilitated the total synthesis of <b>1</b> and <b>2</b>, respectively, with spectroscopic data highly similar to those of natural products