Heteroacenes, Novel Organic Semiconductors

计划合成更大的并苯类分子(杂并苯)。在杂苯中，一些芳香族C-H基团被吡啶类氮取代。这些小组将探索氮环原子数量的增加对杂苯的光学、电化学和电学性质的影响。为了增加(所提出的并烯类型)的溶解度并加强固体中芳香族分子的相互重叠，它们将安装(三烷基硅基)乙炔基团作为取代基。三烷基硅基促进了杂苯的溶液相加工。合成部分将扩展到卤代氮杂戊烯，因为它们是目前非常感兴趣的电子传输材料，并且可以很容易地通过在路线上制备的中间体来制备。计划对杂苯在固体载体上的薄膜形成进行广泛的研究。这些薄膜将通过显微镜和光谱方法进行检查；这些小组计划通过有机配体来修饰下表面，以控制所建议的杂苯的堆积和堆积，以优化其平行和垂直于表面的电学性能，并展望在有机电子领域的潜在应用。提出的杂苯是用于n沟道薄膜晶体管的电子导电材料。杂并苯应该具有与并五苯(最重要的有机半导体)类似的电学性质。它们可以传输电子，而不是正电荷(空穴)。杂苯有可能构建具有反向极性和反向电流的有机电子器件。这种反极性薄膜晶体管在先进的发光二极管和固态照明设备中作为驱动器具有广泛的重要性。PI已经建立了与少数族裔高中合作的记录，并在HBCU(克拉克·亚特兰大)教授高级有机化学课程。计划在这一赠款期间继续开展这些活动。

The synthesis of larger acene-like molecules (heteroacenes) is planned. In the heteroacenes, some of the aromatic C-H groups are substituted by pyridine-type nitrogens. The groups will probe the influence of an increasing number of nitrogen ring atoms on the optical, electrochemical and electrical properties of the heteroacenes. To increase the solubility (of the proposed acene-types) and enforce mutual overlap of the aromatic molecules in the solid state,they will install (trialkylsilyl)ethynyl groups as substituents. The trialkylsilyl groups facilitate the solution-phase processing of the heteroacenes. The synthesis part will be expanded towards halogenated azapentacenes as these are of great current interest as electron transport materials and can be made readily by intermediates that are prepared en route. A broad investigation of the thin film formation of the heteroacenes on solid supports is planned. These thin films will be examined by microscopy and spectroscopic methods; the groups plan to modify the underlying surfaces by organic ligands to control the stacking and packing of the proposed heteroacenes to optimize their electric properties parallel and perpendicular to the surface and envision potential applications in organic electronics. The proposed heteroacenes are electron conducting materials for n-channel thin film transistors. The heteroacenes should have similar electric properties to pentacene (the most important organic semiconductor). They can transport electrons instead of positive charges (holes). Heteroacenes potentially allow the construction of organic electronic devices with reverse polarity and reverse flow of current. Such reversed-polarity thin film transistors are of broad importance as drivers in advanced light emitting diodes and solid-state lighting devices. The PI has established a track record for working with minority high schools and has taught an advanced organic chemistry class at an HBCU (Clark Atlanta). It is planned to continue these activities during this grant period.