All-Fullerene Electron Donor-Acceptor Conjugates
All-Fullerene Electron Donor-Acceptor Conjugates
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DOI：
10.1002/anie.201901863
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发表时间：
2019-05-20
影响因子：
16.6
通讯作者：
Martin, Nazario
中科院分区：
文献类型：
--
作者：
Izquierdo, Marta;Platzer, Benedikt;Martin, Nazario
通过在Lu3N@I-h-C-80和C-60上的偶氮亚胺酰基连续1,3-偶极环加成反应，合成并表征了共价全富勒烯C-60-Lu3N@I-h-C-80电子给体-受体共轭物。据我们所知，这是第一次两个富勒烯同时作为电子供体（Lu3N@I-h-C-80）和受体（C-60）形成电活性哑铃。DFT计算发现了16对非对映体，8对正取向和8对反取向，其中反rsss异构体最稳定。光谱电化学吸收和飞秒瞬态吸收实验支持C-60(.-)-Lu3N@I-h-C-80(。形成+)电荷分离态。电荷分离单重态C-60（.-）的自旋转换-Lu3N@I-h-C-80(。由lu3n -团簇产生的重原子效应促进了+)进入相应的三重态，而重原子效应反过来又使电荷复合速度减慢了一个数量级。
The synthesis and characterization of a covalent all-fullerene C-60-Lu3N@I-h-C-80 electron donor-acceptor conjugate has been realized by sequential 1,3-dipolar cycloaddition reactions of azomethine ylides on Lu3N@I-h-C-80 and C-60. To the best of our knowledge, this is the first time that two fullerenes behaving as both electron donor (Lu3N@I-h-C-80) and acceptor (C-60) are forming an electroactive dumbbell. DFT calculations reveal up to 16 diastereomeric pairs, that is, 8 with syn and 8 with anti orientation, with the anti-RSSS isomer being the most stable. Spectroelectrochemical absorption and femtosecond transient absorption experiments support the notion that a C-60(.-)-Lu3N@I-h-C-80(.+) charge-separated state is formed. Spin conversion from the charge-separated singlet state C-60(.-)-Lu3N@I-h-C-80(.+) into the corresponding triplet state is facilitated by the heavy-atom effect stemming from the Lu3N-cluster, which, in turn, slows down the charge recombination by one order of magnitude.