Electrophilic aromatic substitution. Part 18. Protiodetritiation of anthracene, coronene (dibenzo[ghi,pqr]perylene), and triphenylene in anhydrous trifluoroacetic acid
Electrophilic aromatic substitution. Part 18. Protiodetritiation of anthracene, coronene (dibenzo[ghi,pqr]perylene), and triphenylene in anhydrous trifluoroacetic acid
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亲电芳族取代。
DOI：
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发表时间：
1977
期刊：
影响因子：
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通讯作者：
R. Taylor
中科院分区：
文献类型：
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作者：
H. Ansell;M. Hirschler;R. Taylor
本发明描述了一种测定在无水三氟乙酸中溶解度很低的芳烃的芳氢交换速率的方法。对少至0.05 mg的芳香族化合物进行动力学试验，得到以下部分速率因子（括号中的位置）：蒽，7 900（1）; 1 135（2）; 1.27 × 107（9）;晕苯，7 400（1）;苯并菲，620（1）; 136（2）。相应的σ+值为-0.445。-0.35、-0.81、-0.44、-0.315和-0.24。这是首次定量测定蒽的亲电芳香反应活性，表明1-和2-位比萘中相应位置的反应活性更高，但这些位置的反应活性比萘中的那些位置更接近。这两种效果预测的计算也正确地预测苯并菲和晕苯的反应性，交换结果证实，苯并菲的硝化给出异常速率数据。
A method is described for determining aromatic hydrogen exchange rates in anhydrous trifluoroacetic acid for aromatic hydrocarbons of very low solubility. Kinetic runs, carried out on as little as 0.05 mg of aromatic compound, lead to the following partial rate factors (positions in parentheses): anthracene, 7 900(1); 1 135(2); 1.27 × 107(9); coronene, 7 400(1); triphenylene, 620(1); 136(2). The corresponding σ+ values are –0.445. –0.35, –0.81, –0.44, –0.315, and –0.24. This, the first quantitative determination of the electrophilic aromatic reactivity of anthracene, shows that the 1- and 2-positions are more reactive than the corresponding positions in naphthalene, but these position are closer in reactivity than are those in naphthalene. Both effects are predicted by calculations which also correctly predict the reactivity of triphenylene and coronene; the exchange results confirm that the nitration of triphenylene gives anomalous rate data.