An efficient process involving the catalytic kinetic resolution of racemic spiro‐epoxyoxindoles with the simultaneous enantioselective Friedel–Crafts alkylation of indoles has been realized using a chiral phosphoric acid catalyst. The reaction pro...
An efficient process involving the catalytic kinetic resolution of racemic spiro‐epoxyoxindoles with the simultaneous enantioselective Friedel–Crafts alkylation of indoles has been realized using a chiral phosphoric acid catalyst. The reaction provides two useful intermediates in high yields and excellent enantioselectivities. Performing the catalysis on a gram scale led to (R)‐3‐(3‐indolyl)‐oxindole‐3‐methanol, which was used in the asymmetric formal total synthesis of (+)‐gliocladin C. Notably, the enantiomers (S)‐3‐(3‐indolyl)‐oxindole‐3‐methanol can be obtained easily by the reaction of the resolved spiro‐epoxyoxindole with indole.
Ein effizientes Verfahren zur kinetischen Racematspaltung von Spiroepoxyoxindolen unter enantioselektiver Friedel‐Crafts‐Alkylierung mit einem chiralen Phosphorsäurederivat als Katalysator liefert zwei nützliche Zwischenstufen in hohen Ausbeuten und hervorragenden Enantioselektivitäten. Eines der Produkte wurde in einer asymmetrischen formalen Totalsynthese von (+)‐Gliocladin C verwendet.