A new strategy is proposed for the synthesis of tetraether derivatives of calix[4]arenes bearing at the wide rim nitro and phthalimido groups in well defined positions. Since both groups are precursors of amino functions, calix[4]arenes substituted by different N-acylamino residues are easily available in four steps. The essential steps during the synthesis of the precursor consist in the protection of amino groups by the formation of their phthalimides followed by ipso-nitration of the remaining tert-butylphenol ether units. This nitration occurs without side reactions at the phthalimido substituted units, in contrast to simple N-acyl derivatives.
提出了一种新的合成策略,用于在宽口环上的特定位置引入硝基和邻酰
苯胺基的卡立克斯[4]
芳烃四醚衍
生物。由于这两种基团都是
氨基功能的前体,因此经不同的N-酰基
氨基取代的卡立克斯[4]
芳烃四醚很容易在四个步骤内获得。合成前体的关键步骤是通过形成它们的邻酰
苯胺酰基来保护
氨基团,然后对剩余的叔丁基
酚醚单元进行ipso-硝化。与简单的N-酰基衍
生物相比,这种硝化不会在邻酰
苯胺基取代单元发生副反应。