Enantioselective synthesis of 1,2,5,6-tetrahydropyridines (THPs) via proline-catalyzed direct Mannich-cyclization/domino oxidation–reduction sequence: application for medicinally important N-heterocycles
作者:Panduga Ramaraju、Nisar A. Mir、Deepika Singh、Indresh Kumar
DOI:10.1039/c6ra12965j
日期:——
An enantioselective multi-component synthesis of 1,2,5,6-tetrahydropyridines (THPs) has been developed through a one-pot domino-process. This transformation proceeds through proline-catalyzed direct Mannich reaction-cyclization of glutaraldehyde with in situ generated imines, followed by site-selective oxidation–reduction sequence under mild conditions. Chiral 1,2,5,6-THPs are obtained in good to high
通过一锅多米诺法开发了1,2,5,6-四氢吡啶(THP)的对映选择性多组分合成方法。这种转化通过脯氨酸催化戊二醛与原位生成的亚胺的直接曼尼希反应环化进行,然后在温和条件下进行定点选择性氧化还原序列。手性1,2,5,6-THP的收率高至高(高达80%),并且具有出色的对映选择性(高达98:2 er)。还显示了这种操作简单的方法的有用性,可以合成其他医学上重要的氮杂环。