A dehydrogenation route to azomethine ylides and isoindoles
Abstract
Dehydrogenation of methyl 1,2,3,4-tetrahydroisoquinolin-2-yl- and β-carbolin-9-yl-acetates with palladium black in dimethylformamide generates anti-azomethine ylides stereospecifically. The analogous reaction with methyl isoindolin-2-ylacetate gives the corresponding isoindole. Both types of product can be trapped by N-methylmaleimide. The mechanism of the dehydrogenation processes is discussed.