本文選題：二硫化二苯并噻唑 + 氧化偶聯(lián)　； 參考：《鄭州大學(xué)》2017年碩士論文

【摘要】：隨著人們環(huán)保意識(shí)的增強(qiáng),綠色化學(xué)越來(lái)越受到化學(xué)家的關(guān)注。本論文將以綠色化學(xué)為原則,進(jìn)行硫醇氧化偶聯(lián)反應(yīng)新方法的建立。氧氣作為一種清潔無(wú)污染的氧化劑一直受到化學(xué)家的青睞,然而單純的氧氣對(duì)于許多的化學(xué)反應(yīng)并不能起到直接的氧化作用,而是在反應(yīng)中加入一些催化劑或者其他媒介來(lái)促使氧氣參與到化學(xué)反應(yīng)中去,從而起到氧化作用。TEMPO廣泛的應(yīng)用于催化氧化化學(xué)方面,尤其在醇的選擇性催化氧化上最為出色,在催化硫醇氧化也展現(xiàn)出很好活性。在本文中,我們采用了一種高活性的有機(jī)小分子催化劑2,2,6,6-四甲基哌啶-N-氧自由基(TEMPO)來(lái)實(shí)現(xiàn)硫醇在分子氧下的氧化反應(yīng)。硫-硫鍵的形成已經(jīng)為人們所熟知,其在自然界也已經(jīng)被發(fā)現(xiàn)存在于許多生物體內(nèi)。S-S鍵在生物體中對(duì)于一些蛋白質(zhì)的形成至關(guān)重要,同時(shí)也發(fā)現(xiàn)其在生物醫(yī)藥方面具有一些特殊的作用,例如一些具有硫硫鍵的化合物已經(jīng)被發(fā)現(xiàn)具有抗腫瘤的特性,對(duì)于癌癥的治療具有重大意義。在工業(yè)上一些含有硫硫鍵的化學(xué)品如二硫化二苯并噻唑,已經(jīng)用作硫化橡膠促進(jìn)劑,且效果很好。還有具有S-S鍵的一些聚合物已經(jīng)被研究用于可充電電池,并已經(jīng)取得了一定的進(jìn)展。在文中我們主要研究硫硫鍵的形成。為人們所熟知的硫化橡膠促進(jìn)劑二硫化二苯并噻唑已經(jīng)在工業(yè)上進(jìn)行生產(chǎn),在合成上采用的常見(jiàn)方法有次氯酸鈉氧化,氯氣氧化,亞硝酸鈉氧化,雙氧水氧化等,這些方法主要有一些缺點(diǎn)如反應(yīng)條件不溫和,反應(yīng)過(guò)程有毒性金屬試劑參與,反應(yīng)后產(chǎn)生大量廢液等。因此我們?cè)谘芯恐惺褂醚鯕膺@一綠色氧化劑,在反應(yīng)中加入TEMPO作為催化劑,對(duì)二硫化二苯并噻唑的合成進(jìn)行了一系列的研究,在實(shí)驗(yàn)過(guò)程中研究了反應(yīng)溫度、溶劑、催化劑用量、氧壓、反應(yīng)時(shí)間和反應(yīng)濃度等因素對(duì)反應(yīng)的影響。最終,反應(yīng)最優(yōu)條件確定為2-巰基苯并噻唑0.5 mmol,60℃,0.3 MPa氧壓,5 mol%TEMPO催化劑,溶劑乙腈2 m L,反應(yīng)時(shí)間4 h。反應(yīng)收率達(dá)到97%。我們以構(gòu)建S-S鍵為目標(biāo),接著又深一步進(jìn)行了研究,對(duì)具備巰基的其他底物如芳基硫酚、雜環(huán)芳基硫酚、烷基硫酚進(jìn)行其自身氧化偶聯(lián)反應(yīng)的研究,皆能得到中等到高產(chǎn)率的目標(biāo)產(chǎn)物。鑒于對(duì)交叉偶聯(lián)反應(yīng)報(bào)道不多,我們對(duì)不同巰基底物進(jìn)行了交叉偶聯(lián)反應(yīng),研究發(fā)現(xiàn)芳基硫酚交叉偶聯(lián)產(chǎn)率很高,烷基硫酚進(jìn)行交叉S-S偶聯(lián)得到中等產(chǎn)率。
[Abstract]:With the increasing awareness of environmental protection, green chemistry has been paid more and more attention by chemists. In this paper, a new method of oxidative coupling reaction of mercaptan will be established based on green chemistry. Oxygen has been favored by chemists as a clean and pollution-free oxidant. However, pure oxygen does not directly oxidize many chemical reactions. Instead, some catalyst or other medium is added to the reaction to induce oxygen to take part in the chemical reaction, thus providing oxidation. TEMPO is widely used in catalytic oxidation chemistry, especially in the selective catalytic oxidation of alcohols. It also showed good activity in catalytic mercaptan oxidation. In this paper, a kind of high activity organic small molecule catalyst 2O2O2O6O6 tetramethylpiperidine-N- oxygen free radical (TEMPO) was used to realize the oxidation of mercaptan under molecular oxygen. The formation of sulfur-sulfur bonds has been well known, and it has been found in nature that the. S-S bond in many organisms is essential for the formation of some proteins. At the same time, it has been found that it has some special functions in biomedicine. For example, some compounds with sulfur and sulfur bond have been found to have anti-tumor properties, which is of great significance for the treatment of cancer. Some chemicals containing sulfur and sulfur bonds, such as dibenzothiazole disulfide, have been used as accelerators for vulcanized rubber. Some polymers with S-S bond have been studied for rechargeable batteries and some progress has been made. In this paper, we mainly study the formation of sulfur and sulfur bonds. The accelerator of vulcanized rubber, dibenzothiazole disulfide, has been produced in industry. The common methods used in synthesis are sodium hypochlorite oxidation, chlorine oxidation, sodium nitrite oxidation, hydrogen peroxide oxidation and so on. The main disadvantages of these methods are that the reaction conditions are not mild, toxic metal reagents are involved in the reaction process, and a large amount of waste liquid is produced after the reaction. Therefore, we used oxygen as a green oxidant and TEMPO as catalyst to study the synthesis of dibenzothiazole disulfide. The reaction temperature and solvent were studied. The effects of catalyst dosage, oxygen pressure, reaction time and reaction concentration on the reaction were investigated. Finally, the optimum reaction conditions were determined as follows: 2-mercaptobenzothiazole 0.5 mmol / L 60 鈩，

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