Highly efficient one-pot C-, N- and O-acylation of indolin-2-one analogs

A highly efficient one-pot multiple acylation at chemically non-equivalent sites on indolin-2-one and related motifs using 4-(N,N-dimethylamino)pyridine as a catalyst is described. This procedure gives extremely facile entry to highly desired 3-acyl-2-hydroxy-indole synthons among other derivatives.