Pd-Catalyzed solvent-controlled site-selective arene C-H monoacyloxylation of pyrrolo[2,3-d]pyrimidine derivatives.

An efficient and highly regioselective Pd-catalyzed direct arene C(sp2)-H acyloxylation of pyrrolo[2,3-d]pyrimidine derivatives is reported. The key strategy involves the utilization of the unique reactivity of pyrrolo[2,3-d]pyrimidine and the employment of pyrrolo[2,3-d]pyrimidine as the directing group. A variety of monoacyloxylated pyrrolo[2,3-d]pyrimidine derivatives can be achieved by switching the solvents under mild conditions, and they can be further modified and exhibit various biological activities.