Regiospecific Synthesis of Substituted 2‐Nitrobenzaldehydes from Benzaldehydes through Palladium‐Catalyzed Chelation‐Assisted C–H Nitration
A regiospecific synthesis of substituted 2-nitrobenzaldehydes from substituted benzaldehydes has been developed that involves a three-step process with palladium-catalyzed chelation-assisted C–H nitration as the key step. In the process, O-methyl aldoxime serves as a removable directing group for the palladium-catalyzed ortho-nitration of substituted benzaldoximes and it can be removed in subsequent conversion of the resulting 2-nitrobenzaldoximes into 2-nitrobenzaldehydes.