Development of Organic Conductors with Self-Assembled Architectures of Biomolecules: Synthesis and Crystal Structures of Nucleobase-Functionalized Tetrathiafulvalene Derivatives
摘要:
研究了新型核苷碱功能化的四硫富瓦烯(TTF)衍生物的超分子聚集体和电荷转移复合物。通过斯蒂尔反应,三正丁基锡化的TTF与碘化核苷碱衍生物之间进行了交叉偶联反应,产生了单核苷碱和双核苷碱取代的TTF衍生物。电化学测量表明,取代有尿嘧啶和胞嘧啶的衍生物具有强的电子给体能力, comparable 于纯净的TTF,而腺嘌呤和鸟嘌呤的电子缺乏特征导致了氧化波的高电位移。在溶液态的电子光谱中,观察到了低能量区域的分子内电荷转移吸收带。在晶体结构中,供体分子通过核苷碱固有的互补氢键构建了超分子聚合物;腺嘌呤取代的衍生物形成了一维之字形链,而二尿嘧啶取代的衍生物形成了一条线性链。取代有尿嘧啶和胞嘧啶的四氰基奎烯和二烯复合物具有混合价态,表现出高电导率(室温电导率 = 10−2–10−1 S cm−1)。在氰苯基酸复合物中,胞嘧啶和腺嘌呤取代的TTF作为电子供体和质子受体,形成了同时进行电荷和质子转移的复合物。
Development of Organic Conductors with Self-Assembled Architectures of Biomolecules: Synthesis and Crystal Structures of Nucleobase-Functionalized Tetrathiafulvalene Derivatives
Supramolecular assemblies and charge-transfer complexes of new nucleobase-functionalized tetrathiafulvalene (TTF) derivatives were investigated. Stille-type cross-coupling reaction between tributylstannylated TTF and iodinated nucleobase derivatives yielded mono- and bisnucleobase-substituted TTF derivatives. The electrochemical measurements revealed that the uracil- and cytosine-substituted derivatives possessed strong electron-donating abilities comparable to that of pristine TTF, and the electron-deficient features of adenine and guanine caused high potential shifts of the oxidation waves. In the solution-state electronic spectra, the intramolecular charge-transfer absorption bands were observed at a low-energy region. In the crystal structures, the donor molecules constructed supramolecular polymers by the complementary hydrogen-bonds inherent in nucleobases; a one-dimensional zigzag chain in the adenine-substituted derivative and a linear chain in the bis(uracil)-substituted derivative. The tetracyanoquinodimethane complexes of uracil- and cytosine-substituted derivatives possessed a mixed valence state exhibiting high conductivities (room-temperature conductivities = 10−2–10−1 S cm−1). In the cyananilic acid complexes, cytosine- and adenine-substituted TTF acted as electron-donors and proton-acceptors to yield simultaneous charge- and proton-transfer complexes.
研究了新型核苷碱功能化的四硫富瓦烯(TTF)衍生物的超分子聚集体和电荷转移复合物。通过斯蒂尔反应,三正丁基锡化的TTF与碘化核苷碱衍生物之间进行了交叉偶联反应,产生了单核苷碱和双核苷碱取代的TTF衍生物。电化学测量表明,取代有尿嘧啶和胞嘧啶的衍生物具有强的电子给体能力, comparable 于纯净的TTF,而腺嘌呤和鸟嘌呤的电子缺乏特征导致了氧化波的高电位移。在溶液态的电子光谱中,观察到了低能量区域的分子内电荷转移吸收带。在晶体结构中,供体分子通过核苷碱固有的互补氢键构建了超分子聚合物;腺嘌呤取代的衍生物形成了一维之字形链,而二尿嘧啶取代的衍生物形成了一条线性链。取代有尿嘧啶和胞嘧啶的四氰基奎烯和二烯复合物具有混合价态,表现出高电导率(室温电导率 = 10−2–10−1 S cm−1)。在氰苯基酸复合物中,胞嘧啶和腺嘌呤取代的TTF作为电子供体和质子受体,形成了同时进行电荷和质子转移的复合物。
Redox-active tubular frameworks with TTF: self-assemblies by complementary hydrogen-bonds and π-stacks of TTF-phenyluracil
Tubular frameworks of a tetrathiafulvalene (TTF) based electron-donor with a N1-phenyluracil moiety were constructed by strong self-assembling abilities. The uracil moiety formed the reversed WatsonâCrick type hydrogen-bond pair. The TTF moiety exhibited CâHâ¯X hydrogen-bonds, Sâ¯S interactions, and uniform Ï-stack. The phenyl group formed a herring-bone array by the edge-to-face interaction. These multiple intermolecular interactions established channels of ca. 4 à 8 à . The cavities were filled with crystalline solvent molecules (tetrahydrofuran and pyridine), which were fixed on the framework by the CâHâ¯X hydrogen-bonds.