利用一價溴化銅區位選擇活化4-pyridone及uracil衍生物 碳氫鍵進行芳基化反應

Regioselective Arylation of Uracil and 4-Pyridone Derivatives via Copper(I) Bromide Mediated C-H Bond Activation

程健(Chien Cheng)

指導教授 ： 簡敦誠

國立臺灣師範大學/理學院/化學系/碩士(2012年)

摘要

尿嘧啶核苷 (uridine) 在 5-位或 6-位上含有芳香環取代的類似物是嘧啶核苷酸 (pyrimidine nucleotides) 中重要的一類衍生物，近年逐漸地受到重視。但 6-aryluridines 合成及應用的相關文獻卻非常有限。

一般而言，在 uridine 的 6-位中引進芳基團，僅限於以下兩種方式：(1) 在 6-iodouridines 上利用光化學 (photochemical) 進行芳基化反應；(2) 在 6-iodouridines 利用 Suzuki-Miyaura 和 Stille 交叉耦合 (cross-coupling) 進行芳基化 (arylation) 反應。但 6-iodouridines 製備困難，而限制了此方法的應用性。

在過去十年間，直接針對 C-H (碳-氫) 鍵活化而進行 arylation 逐漸成熟，因此可應用在多種芳香環及雜芳香環上。而本論文研究即針對 uracil 和 4-pyridone 與 aryl iodides 直接將 C-H 鍵活化，進行交叉耦合反應。

因此，我們報導實用且一般性的合成，利用 1,3-dimethyluracil 及其衍生物作為 uridine 的模型，藉由銅金屬 (copper) 催化經由 C-H 鍵的活化而合成 6-aryl-1,3-DMU 的衍生物。此外，利用同位素效應的研究，更進一步地了解反應的細節，並經由同位素效應的實驗數據，推測出可能的反應機制。

關鍵字

碳氫鍵活化

並列摘要

C-Aryl-substituted uridine derivatives are an important class of pyrimidine nucleoside analogs that has received considerable attention in recent years. Very few examples of 6-aryluridines have been reported in the literature.

In general, the introduction of an aryl group at 6-position of uracil was limited to the following two ways: (1) photochemical arylation from the 6-iodouridines. (2) Suzuki-Miyaura and Stille cross-coupling reaction from 6-iodouridines. Both methods were restricted by the difficulty for the preparation of 6-iodouridines.

In the past decade, the direct C-H activation for arylation has become an effective method for the introduction of diverse aromatic and heteroaromatic substituents. The focus of this thesis was to develop an effective method which could directly activate the C-H on the uracil or 4-pyridone to undergo the coupling reaction with aryl iodides.

Herein, we reported a general and practical synthesis of 6-aryl-1,3-dimethyluracil derivatives from 1,3-dimethyluracil (1,3-DMU) derivatives via the copper-mediated C-H bond activation as a reaction model for uridine. The reaction scope is generally applicable to a variety of uracil derivatives. In addition, the deuterium isotope studies were carried out in order to gain insight into the reaction details. A preliminary reaction mechanism was proposed based on the isotope effect data.

並列關鍵字

C-H activation

參考文獻

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