铜（II）化合物作用下2-綦胺的氧化偶合反应

2-萘胺（1）在甲醇中与铜胺络合物x(CuCl_2):x(苄胺或乙醇胺）=2：1]室温 下反应得到产率为74%的1,1'-联-2-萘胺（2）。在醋酸铜、硝酸铜或高氯酸铜的催 化下，1在甲醇中被氢气氧化为2-氨基-1，4-萘醌-4-2'-萘亚胺（3），产率86%。 用X-ray单晶衍射证实3的乙酰化产物结构为2-乙酰氨基-1，4-萘醌-E-4-2'-萘亚胺 （4）。循环伏安研究表明，铜（II）化合物的氧化反应选择性与其还原峰电位有 关。电喷雾质谱的分析表明1，2-萘醌-2-亚胺（6）是生成3的中间体。

Copper(II)-Mediated Oxidative Coupling of 2-Naphthylamine

An efficient synthesis of 2,2'-diamino-1,1'-binaphthalene (2) from 2-naphthylamine (1) was carried out at room temperature in methanol by copper-amine mediated oxidative coupling x(CuCl_2):x(benzylamine or ethanolamine) = 2:1, equivalent to 1] for 2 hours. The precipitated complex of 2-CuCl_2 was separated and decomposed to give 2 in 74% yield. The oxidant was CuCl_2-amine while O_2 regenerated Cu(II) by oxidizing the Cu(I) species. The aerobic oxidation of 1 at room temperature in methanol under the catalysis of cupric salt Cu(ClO_4) _2, Cu(NO_3)_2 or Cu(OAc)_2] resulted in 2-amino-1,4- naphthoquinone-4- 2'-naphthylimide (3) with high yield up to 86%. X-Ray single crystal diffraction analysis of the acetylized product of 3 shows that its structure is 2-acetoamino-1,4-naphthoquinone-(E)-4-2'-naphthylimide (4) . Cyclic voltammetry analysis suggests that the selectivity of the oxidation of 1 can be related to the reductive potentials of the copper(II) compounds. The fact that under anaerobic condition 1 is inert to Cu(ClO_4)_2, Cu(NO_3)_2 or Cu(OAc)_2 infers that O_2 acts as the electron acceptor and is activated by Cu(II) to oxidize 1. ESI-MS analysis indicates that the intermediate is 1,2- naphthoquione-2-imide (6), which forms 3 via addition with 1 followed by oxidation.