Development of an Intrinsically Safer Methanolysis/Aromatic Nitro Group Reduction for Step 1 and 2 of Talazoparib Tosylate

A change in facility for the synthesis of the step 2 intermediate for talazoparib tosylate (1·TsOH) required the development of an alternative, intrinsically safer process. Rapid route scouting and considerations of process safety enabled the development of a telescoped two-step process that was demonstrated on a multikilogram scale.