Peripheral Hexabromination, Hexaphenylation, and Hexaethynylation of meso-Aryl-Substituted Subporphyrins

摘要

Effective peripheral fabrication methods of meso-aryl-substituted subporphyrins were explored for the first time. Hexabrominated subporphyrins 2 were prepared quantitatively from the bromination of subporphyrins 1 with bromine. Hexaphenylated subporphyrins 3 and hexaethynylated subporphyrins 4 and 5 were synthesized by Suzuki-Miyaura coupling and Stille coupling, respectively, in good yields. X-ray crystal structures of 2b, 3b, 4b, and 5a revealed preservation of the bowl-shaped bent Structures with bowl depths similar to that of 1. Hexaethynylated subporphyrins exhibit large two-photon-absorption cross-sections clue to effective delocalization of the conjugated network to the ethynyl substituents.