Enantioselective Synthesis of Arene cis-Dihydrodiols from 2-Pyrones.

An enantioselective chemical synthesis of arene cis-dihydrodiols has been realized from 2-pyrones through sequential ytterbium-catalyzed asymmetric inverse-electron-demand Diels-Alder (IEDDA) reaction of 2-pyrones and retro-Diels-Alder extrusion of CO2 . By using this strategy, a series of substituted arene cis-dihydrodiols can be obtained efficiently with high enantioselectivity (>99 % ee in many cases). Based on this strategy, efficient and concise asymmetric total syntheses of (+)-MK7607 and 1-epi-(+)-MK7607 were accomplished.