Abstract

Magnesium tetra(arylethynyl)porphyrins (aryl=Ph or 4‐CF₃C₆H₄) were synthesized via 5,15‐di(triisopropylsilylethynyl)‐10,20‐di(arylethynyl)porphyrin to ensure good solubility and high synthetic yields. Magnesium tetra(phenylethynyl)porphyrin was subjected to structural analyses and physico‐chemical characterization. Single‐crystal X‐ray analysis revealed porous crystal structures featuring solvent molecules in their pores. From femtosecond transient absorption measurements we concluded that the singlet excited‐state lifetime of magnesium tetra(phenylethynyl)porphyrin is with 7.4 ns substantially longer than that of its zinc congener with 2.8 ns; this is attributed to the lower atomic weight of magnesium compared with zinc.