First asymmetric synthesis of orthoquinone monoketal enantiomers via anodic oxidation.
An asymmetric synthesis of orthoquinone monoketals was accomplished using anodic oxidation to convert aryl methyl ethers bearing a chiral ethanol unit into orthoquinone bisketals, followed by monohydrolysis of their dimethyl ketal unit. All four possible stereoisomers were generated in a diastereoselective manner by varying the attachment point of the chiral pro-ketal alcoholic auxiliary to the starting arene. A preliminary screening of subsequent nucleophilic addition reactions confirmed the potential utility of these synthons in asymmetric synthesis. [reaction: see text]
Quideau
Stéphane
S
Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33607 Pessac Cedex, France. s.quideau@iecb.u-bordeaux.fr
Fabre
Isabelle
I
Deffieux
Denis
D