Post-functionalization of tritopic subphthalocyanines with C3v symmetry

The successful applications of subphthalocyanines (SubPcs) in the field of molecular materials largely stem from their unique post-functionalization versatility, where regioisomerism and substitution patterns play critical roles. In this context, chiral tritopic [Formula: see text]- or [Formula: see text]-symmetric SubPcs, as well as more symmetric hexatopic C3v SubPcs, have been extensively explored. However, tritopic derivatives with C3v symmetry represent an appealing yet underexplored family, combining the lower substitution density of the former with the simplified symmetry of the latter. Herein, we explore the post-functionalization of triimide-SubPcs. Specifically, we synthesize a versatile synthon based on triimide-SubPcs equipped with iodoaryl groups. These SubPcs exhibit high sensitivity under the typical reaction conditions employed for cross-coupling reactions, including Suzuki, Sonogashira, and Buchwald-Hartwig protocols. Nonetheless, we optimize Stille cross-coupling conditions, enabling the selective installation of ethenyl and ethynyl substituents on the aryl groups attached to the imide nitrogen atoms. UV-Vis absorption spectroscopy and theoretical calculations reveal that the ethynyl and ethenyl groups do not significantly alter the electronic structure of the SubPc macrocycle. Collectively, this study establishes a pathway toward the synthesis of the largely unexplored yet highly promising family of C3v tritopic SubPcs, expanding the toolbox of SubPc derivatives for advanced molecular materials.