Abstract

Palladium catalysis is a salient synthetic methodology for carbon-carbon bond formation for which the classical procedures have been powerful tools in chemistry for decades. Due to certain limitations, alternative methods for palladium catalyzed cross couplings have been developed, rendering the approach more environmentally sustainable. Notably, the desulfinative cross coupling reaction avoids stoichiometric organometallic waste production. Furthermore, sulfinate salts are functionally versatile as they can act both as an electrophilic or nucleophilic cross coupling partner, and at the same time they are also bench stable and easy to handle. However, as sulfinate salts can undergo self-disproportionation in solution, it limits their further synthetic applications. To overcome the issue, we propose to introduce a removable multiuse moiety to maintain the sulfinic acid. We explore pyridine as a multi-purpose option, due to its directing impact on palladium catalyzed ortho-halogenation. The methodology also translates to ortho-deuteration for the synthesis of useful isotopic compounds with potential value for pharmaceutical research. After ortho-functionalization, the pyridine group can be removed to regain the sulfinic acid moiety for subsequent cross couplings. Combined, these approaches complement existing methodologies in accessing multi-functionalized arene systems.