Near-IR Absorbing Aza-Benzannulated Perylenebisimide-Porphyrin Tape

Aza-benzannulated perylenebisimide (N-PBI)-appended singly- and triply-linked porphyrin dimers have been synthesized and structurally characterized. Single-crystal X-ray diffraction analysis confirmed the structure for the triply-linked dimer, revealing an almost perpendicular arrangement of the two chromophores. The triply linked dimer, designated as ZP3 exhibits an intense and broad absorption band reaching into near-IR region. The excited state photophysical characteristics for the singly- and triply- linked derivatives were investigated using ultrafast transient absorption techniques. ZP3 demonstrated a rapid decay from its photoexcited state in approximately 4 ps due to swift internal conversion, a unique feature of the tape.