Efficient photoinduced electron transfer was observed across a [10]cycloparaphenylene ([10]CPP) moiety that serves as a rigid non-covalent bridge between a zinc porphyrin and a range of fullerenes. The preparation of iodo-[10]CPP is the key to the synthesis of a porphyrin-[10]CPP conjugate, which binds C , C , (C ) , and other fullerenes (K >10 m ). Fluorescence and pump-probe spectroscopy revealed intramolecular energy transfer between CPP and porphyrin and also efficient charge separation between porphyrin and fullerenes, affording up to 0.5 μs lifetime charge-separated states. The advantage of this approach towards electron donor-acceptor dyads is evident in the case of dumbbell-shaped (C ) , which gave intricate charge-transfer behavior in 1:1 and 2:1 complexes. These results suggest that [10]CPP and its cross-coupled derivatives could act as supramolecular mediators of charge transport in organic electronic devices.

Efficient photoinduced electron transfer was observed across a[ 10]cycloparaphenylene ([10]CPP) moiety that serves as ar igid non-covalent bridge between az inc porphyrin and ar ange of fullerenes.The preparation of iodo-[10]CPP is the key to the synthesis of ap orphyrin-[10]CPP conjugate,w hich binds C 60 ,C 70 ,( C 60 ) 2 ,a nd other fullerenes (K A > 10 5 m À1 ). Fluorescence and pump-probe spectroscopy revealed intramolecular energy transfer between CPP and porphyrin and also efficient charge separation between porphyrin and fullerenes,a ffording up to 0.5 msl ifetime chargeseparated states.T he advantage of this approach towards electron donor-acceptor dyads is evident in the case of dumbbell-shaped (C 60 ) 2 ,w hichg ave intricate charge-transfer behavior in 1:1a nd 2:1c omplexes.T hese results suggest that [10]CPP and its cross-coupled derivatives could act as supramolecular mediators of charge transport in organic electronic devices.

To expand the toolbox of dynamic covalent and systems chemistry, we investigated the acid-catalyzed exchange reaction of trithioorthoesters with thiols. We found that trithioorthoester exchange occurs readily in various solvents in the presence of stoichiometric amounts of strong Brønsted acids or catalytic amounts of certain Lewis acids. The scope of the exchange reaction was explored with various substrates, and conditions were identified that permit clean metathesis reactions between two different trithioorthoesters. One distinct advantage of S,S,S-orthoester exchange over O,O,O-orthoester exchange is that the exchange reaction can kinetically outcompete hydrolysis, thereby making the process less sensitive to residual moisture. We expect that the relatively high stability of the products might be beneficial in future supramolecular receptors or porous materials.

Four new azafullerene monoadducts (DPS-C59N, HDP-C59N, DBOP-C59N, DHOP-C59N) have been prepared and applied as electron acceptors in solution-processed bulk heterojunction solar cells. The four compounds were designed so that their solubility in organic solvents was maximized and that structure–property comparisons could be drawn with a previously synthesized azafullerene electron acceptor. With the photovoltaic devices that were prepared from the four aza­fullerenes and polymeric electron donor PTB7 we found that only one of the four new electron acceptors resulted in a power conversion efficiency that exceeded the one observed with a previously reported aza­fullerene monoadduct. Atomic force microscopy and electron mobility measurements suggest that azafullerenes bearing two alkyl chains lead to non-optimal film morphologies as well as electron mobilities and that future efforts should focus on single n-alkyl substitution.