碳材料可因具有不同鍵結結構而有不同的電子傳導性和熱力學穩定性，例如石墨烯、奈米管和石墨烯量子點等，即因其獨特的光電特性而備受關注。本研究探討以有機合成策略開發結構明確的單層石墨烯類材料，詳細分析每個合成反應步驟的重要參數和中間產物的光物理性質。所探討合成奈米石墨烯前驅物的策略為通過鈀催化的 Sonogashira 偶聯、甲矽烷基脫保護、Diels-Alder 環化和環三聚反應，從小分子 4,4'-二溴苯基丙烯酰基逐步合成大分子量的聚合多環芳香烴(C222H150)。
首先，在Sonogashira 偶聯反應步驟比較不同的反應條件的影響，結果顯示惰性氣體環境及催化劑是重要的反應條件。在 80°C 下連續攪拌 4,4'-二溴苯乙炔、5% Pd(PPh3)2Cl2、10% CuI、3當量的三甲基甲矽烷基乙炔和10% PPh3 的混合物 5 小時，經過管柱層析法獲得純目標產物的產率可達 30%。
在第二步和第三步反應過程中，依目前的反應參數條件，無需進一步純化即可得到目標產物，產率分別為100 %和87 %。 第四步反應採用10 %八羰基二鈷催化劑，需在高溫下長時間反應（5天）即可生成產物。 產品的純化可藉由先將反或獲得混合物與少量二氧化矽預混合後，再流經層析管柱來完成。目前經過四個反應合成步驟後的C222H150總產率為6.25%，多環芳香烴產品為白色固體。
以PL光譜分析每個反應步驟的中間產物的光學特性，發現各個合成步驟的產物皆具有藍色發光特徵，溶液形式的激發和發射波長較固體樣品更短，未來可以進一步探討這些中間產物的光物理和光化學分析並應用於太陽能光電有機材料。

Carbon material has tunable electronic, and thermodynamic stability with varying molecular structure. Graphene, nanotube, and graphene quantum dots are of high interest for applications of their unique optoelectronic properties. In this study, organic synthesis strategy for developping well-defined single layer graphene-like material, the important parameters of each reaction steps and the intermediate products photophysical properties are examined. The step wise synthesis strategy of large polyphenylene (C222H150) as nanographene precursors from small molecule 4,4’-dibromophenylacateylene via palladium-catalyzed Sonogashira coupling, silyl de-protection, Diels-Alder cyclization and cyclotrimerization reaction is carefully studied.
The first step, Sonogashira coupling reaction were attempted in several reaction conditions which very dependent on inert atmosphere and catalysts. The best isolated yield obtained is 30% as pure product by continuous stirring the mixture of 4,4’-dibromophenylacetylene, 5% Pd(PPh3)2Cl2, 10% CuI, 3 eq trimethylsilylacetylene, 10% PPh3, at 800C in 5 hours. The column chromatography is a mandatory process to get the pure product.
The second and the third reaction step process, can afford the product without further purification process in high yield (100% and 87% respectively). The fourth step reaction can produce the product using small amount (10%) of dicobaltoctacarbonyl catalyst under high temperature in long time reaction (5 days). The purification of the product can be done using column chromatography by pre-depositing the mixture in a small amount of silica before the column. The total product yield after four-step synthesis is 6.25% with a white solid as polyphenylene product.
The photoluminescence analysis found that the intermediate product from each reaction steps results in shorter excitation and emission wavelength in solution form. The further photophysical and photochemical analysis of the intermediate products can be explore in the future for the organic material photovoltaics applications.

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