A chemo-, regio-, and stereoselective FeCl(3)/1,10-phenanthroline-catalyzed cross dehydrogenative coupling (CDC) reaction between phenols and α-substituted β-ketoesters was developed. The reaction creates a new quaternary carbon center within a polycyclic hemiacetal or polycyclic spirolactone architecture. The applicability of the new method to the synthesis of natural products was demonstrated by a possible biomimetic synthesis of the lachnanthospirone core.