The nitration of α- and β- acylnaphthalenes with copper(II) nitrate in acetic anhydride or nitric acid/acetic acid mixtures gives high yields of the corresponding mononitro compounds. The assignment of constitution to these products is made on the basis of extensive 1H n.m.r. chemicl shift and coupling constant data. In the case of α- acylnaphthalenes, with the notable exception of α- pivalonaphthone, nitration occurs in the α-positions of the unsubstituted ring to give mixtures of 5- and 8-nitro compounds. α- Pivalonaphthone gives appreciable amounts of the 4-nitro compound and also of the 8-nitro compound. This result indicates that the pivaloyl group does not shield the 8-position sterically to any significant extent and is effectively electronically neutral, unlike the other acyl substituents , in allowing attack at the α-position (position 4) of the acylated ring. This result is ascribable to the lack of coplanarity of the pivaloyl group with the naphthalene system. All of the β- acylnaphthalenes gave mixtures of 4-, 5- and 8-nitro derivatives in proportions that did not vary significantly with the nature of the acyl group.
在醋酸酐或硝酸/醋酸混合物中用硝酸铜(II)硝化 α- 和 β-酰基萘,可以得到高产率的相应单硝基化合物。根据大量的 1H n.m.r.化学位移和耦合常数数据,对这些产物的组成进行了分配。在 α-酰基萘的情况中,除了 α-新戊萘酮外,未取代环的α-位都发生了硝化反应,生成 5-和 8-硝基化合物的混合物。这一结果表明,与其他酰基取代基不同,新戊酰基团不会在很大程度上对 8-位进行立体屏蔽,而且实际上是电子中性的,允许对酰化环的α-位(第 4 位)进行攻击。这一结果可归因于新戊酰基团与萘系统缺乏共面性。所有的 β-酰基萘都产生了 4-、5-和 8-硝基衍生物的混合物,其比例随酰基的性质变化不大。