開發(fā)新型N,N-雙齒配體及其鈀配合物在交叉偶聯(lián)反應(yīng)中的應(yīng)用
發(fā)布時(shí)間：2019-03-27 12:19
【摘要】：過(guò)渡金屬催化的成鍵反應(yīng)是有機(jī)合成化學(xué)的前沿,其中偶聯(lián)反應(yīng)是構(gòu)建碳碳、碳雜原子鍵最有效的方法之一。Suzuki反應(yīng)和Heck反應(yīng)是多種偶聯(lián)反應(yīng)中應(yīng)用最廣泛的兩類反應(yīng)。催化劑在反應(yīng)中起著至關(guān)重要的作用,而配體通過(guò)調(diào)節(jié)改善中心金屬的電子、空間環(huán)境從而起到活化金屬的催化活性、延長(zhǎng)催化劑壽命等作用,因此,開發(fā)新型配體一直是開發(fā)高效催化劑的研究重點(diǎn)。常用的配體通常是含有孤對(duì)電子的O、N、P、S等的有機(jī)化合物。N配體金屬催化劑在催化反應(yīng)中顯示了良好的催化活性,但在Pd催化的偶聯(lián)反應(yīng)中催化活性比P配體催化劑存在顯著差異。通常認(rèn)為P配體更容易在電子效應(yīng)和空間效應(yīng)方面進(jìn)行修飾,而且P和金屬之間還存在p反饋?zhàn)饔�。但�?氮配體通常對(duì)水、氧不敏感,相對(duì)容易合成,這些特點(diǎn)對(duì)化學(xué)家們?nèi)猿錆M吸引力。本論文在簡(jiǎn)述雙齒氮配合物及其在偶聯(lián)反應(yīng)等應(yīng)用的研究進(jìn)展基礎(chǔ)上,重點(diǎn)展開以下三個(gè)方面的研究成果1.從電子效應(yīng)和位阻效應(yīng)角度考慮,以5,6,7-三氫喹啉-8-酮、胺、PdCl_2為原料,設(shè)計(jì)并合成了5,6,7-三氫-8-亞胺喹啉系列Pd配合物。方法有分步合成和一鍋法兩種,通過(guò)對(duì)Pd催化劑的結(jié)構(gòu)表征,尤其是單晶X-衍射,得知亞胺上的芳基的位阻效應(yīng)和電子效應(yīng)對(duì)催化劑的結(jié)構(gòu)影響很大。2.將新合成的催化劑Pd1-Pd6,應(yīng)用于Suzuki偶聯(lián)反應(yīng)。以對(duì)甲基溴苯和苯硼酸為標(biāo)準(zhǔn)底物優(yōu)化反應(yīng)條件。結(jié)果表明,在甲苯中以碳酸鉀作堿,使用0.001 mol%量的Pd6催化劑能使反應(yīng)完全轉(zhuǎn)化。同時(shí)發(fā)現(xiàn)配體位阻大、供電能力強(qiáng)的Pd5和Pd6,催化活性明顯高于Pd1-Pd4,最高TON值可達(dá)到4.7×10~6。并在優(yōu)化條件下,開展了底物拓展研究。實(shí)驗(yàn)結(jié)果表明,各類芳基溴底物均能獲得很好的收率。3.論文將催化劑Pd6應(yīng)用于Heck偶聯(lián)反應(yīng)。通過(guò)對(duì)溶劑、溫度、苯乙烯用量以及催化劑用量等條件進(jìn)行優(yōu)化。發(fā)現(xiàn)以DMF作溶劑,0.001 mol%量的Pd6,130℃,1.2 eq.苯乙烯條件下,對(duì)位帶給電子基團(tuán)芳基溴代物可以很好地轉(zhuǎn)化為反式產(chǎn)物;適當(dāng)增加催化劑用量或提升溫度,對(duì)位帶吸電子基團(tuán)的芳基溴代物、雜環(huán)溴代物也可以很好地完成C-C偶聯(lián)反應(yīng)。
[Abstract]:Transition metal-catalyzed bonding reaction is the frontier of organic synthesis chemistry, among which coupling reaction is the most effective method to construct carbon and carbon hetero-atomic bonds. Suzuki reaction and Heck reaction are the two most widely used reactions in many coupling reactions. Catalysts play an important role in the reaction, and ligands improve the electron of the central metal by regulating the space environment, thus play an active role in the catalytic activity of the metal, prolong the life of the catalyst and so on, so that the ligand can improve the electron of the center metal and the space environment. The development of new ligands has always been the focus of research on the development of high-efficiency catalysts. Most commonly used ligands are organic compounds such as O, N, P, S, which contain solitary pairs of electrons. N ligand metal catalysts show good catalytic activity in catalytic reactions. However, the catalytic activity of Pd-catalyzed coupling reaction was significantly different than that of P-ligand catalyst. It is generally believed that P ligand is more easily modified in electron and space effects, and there is p feedback effect between P and metal. However, nitrogen ligands are usually insensitive to water and oxygen and are relatively easy to synthesize, which are still attractive to chemists. In this paper, on the basis of summarizing the research progress of binodentate nitrogen complexes and their applications in coupling reactions, the following three aspects of research achievements are focused on. Taking 5,6,7-trihydroquinoline-8-one, amine and PdCl_2 as raw materials, 5,6,7-trihydro-8-imino-quinoline series Pd complexes were designed and synthesized from the point of view of electron effect and steric hindrance effect. The structure of Pd catalyst was characterized by single crystal X-ray diffraction. It was found that the steric and electronic effects of aryl groups on imines had great influence on the structure of the catalyst. 2. The newly synthesized catalyst Pd1-Pd6, was applied to Suzuki coupling reaction. The reaction conditions were optimized by using p-methyl bromobenzene and phenylboric acid as standard substrates. The results showed that the reaction could be completely transformed by using 0.001 mol% Pd6 catalyst with potassium carbonate as base in toluene. At the same time, it was found that the catalytic activities of Pd5 and Pd6, with high ligand hindrance and strong power supply ability were significantly higher than that of Pd1-Pd4, with the highest TON value of 4.7 脳 10 脳 6. Under the optimized conditions, the substrate expansion research was carried out. The experimental results show that all kinds of aryl bromine substrates can obtain good yields. 3. In this paper, the catalyst Pd6 was applied to Heck coupling reaction. The solvent, temperature, styrene dosage and catalyst dosage were optimized. It was found that using DMF as solvent, the Pd6130 鈩，
本文編號(hào)：2448170
[Abstract]:Transition metal-catalyzed bonding reaction is the frontier of organic synthesis chemistry, among which coupling reaction is the most effective method to construct carbon and carbon hetero-atomic bonds. Suzuki reaction and Heck reaction are the two most widely used reactions in many coupling reactions. Catalysts play an important role in the reaction, and ligands improve the electron of the central metal by regulating the space environment, thus play an active role in the catalytic activity of the metal, prolong the life of the catalyst and so on, so that the ligand can improve the electron of the center metal and the space environment. The development of new ligands has always been the focus of research on the development of high-efficiency catalysts. Most commonly used ligands are organic compounds such as O, N, P, S, which contain solitary pairs of electrons. N ligand metal catalysts show good catalytic activity in catalytic reactions. However, the catalytic activity of Pd-catalyzed coupling reaction was significantly different than that of P-ligand catalyst. It is generally believed that P ligand is more easily modified in electron and space effects, and there is p feedback effect between P and metal. However, nitrogen ligands are usually insensitive to water and oxygen and are relatively easy to synthesize, which are still attractive to chemists. In this paper, on the basis of summarizing the research progress of binodentate nitrogen complexes and their applications in coupling reactions, the following three aspects of research achievements are focused on. Taking 5,6,7-trihydroquinoline-8-one, amine and PdCl_2 as raw materials, 5,6,7-trihydro-8-imino-quinoline series Pd complexes were designed and synthesized from the point of view of electron effect and steric hindrance effect. The structure of Pd catalyst was characterized by single crystal X-ray diffraction. It was found that the steric and electronic effects of aryl groups on imines had great influence on the structure of the catalyst. 2. The newly synthesized catalyst Pd1-Pd6, was applied to Suzuki coupling reaction. The reaction conditions were optimized by using p-methyl bromobenzene and phenylboric acid as standard substrates. The results showed that the reaction could be completely transformed by using 0.001 mol% Pd6 catalyst with potassium carbonate as base in toluene. At the same time, it was found that the catalytic activities of Pd5 and Pd6, with high ligand hindrance and strong power supply ability were significantly higher than that of Pd1-Pd4, with the highest TON value of 4.7 脳 10 脳 6. Under the optimized conditions, the substrate expansion research was carried out. The experimental results show that all kinds of aryl bromine substrates can obtain good yields. 3. In this paper, the catalyst Pd6 was applied to Heck coupling reaction. The solvent, temperature, styrene dosage and catalyst dosage were optimized. It was found that using DMF as solvent, the Pd6130 鈩，
本文編號(hào)：2448170
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