A Bis(C60)-Bis(phthalocyanine) Nanoconjugate: Synthesis and Photoinduced Charge Transfer

A novel dimeric phthalocyanine–C60 nanoconjugate, consisting of a bisphthalocyanine core to which two fullerenes are attached, has been prepared. The synthetic strategy implemented the preparation of a diformyl butadiynyl‐bridged bisphthalocynaninatozinc(II) complex by means of palladium‐catalyzed cross‐coupling reactions and subsequent dipolar cycloaddition reactions. Photophysical experiments confirm that an intramolecular electron transfer, namely, from the photoexcited ZnPc moiety to the electron‐accepting C60 unit, governs the overall photoreactivity of the nanoconjugate. Through‐space charge‐transfer interactions facilitated by the close proximity of the ZnPc and the C60 moieties play a decisive role in determining the lifetimes of the charge‐separated state which range from 10−10 to 10−9 seconds. Communicating through space: Intramolecular electron transfer from the photoexcited zinc‐phthalocyanine (ZnPc) moieties to the electron‐accepting C60 units governs the overall photoreactivity of a (ZnPc)2‐(C60)2 tetrad. Through‐space charge‐transfer interactions facilitated by the proximity of the electro‐ and photoactive ZnPc and C60 units influence the lifetimes of the charge‐separated state (10−10–10−9 s).