A dual role for acetohydrazide in Pd-catalyzed controlled C(sp)-H acetoxylation of aldehydes.

The palladium catalyzed aldehyde directed acetoxylation of C(sp)-H bonds was realized by a transient directing group approach for the first time. Crucial to the successful outcome of this reaction is the dual role of acetohydrazide as a directing group for the catalytic C(sp)-H activation process and as a protecting group for the CHO functional group. The applicable methodology exhibits good functional group tolerance and occurs readily under mild conditions.