The first approach to the preparation of 1-unsubstituted 2-arylindolizines by intramolecular 1,5-dipolar cyclization of 2-(2-arylethenyl)pyridinium ylides 2a-v in the presence of tetrakis(pyridine)cobalt (II) dichromate was developed. Several kinds of novel 1-unsubstituted 2-aryl-3-acetyl-, 3-benzoyl-, 3-ethoxycarbonyl- and 3-(4-nitrobenzoyl)indolizines 3a-v were synthesized under the mild conditions in reasonable to moderate yields.
首次开发了在四(
吡啶)重
铬酸钴(II)存在下,通过 2-(2-芳基
乙烯基)
吡啶鎓酰化物 2a-v 的分子内 1,5- 二极环化反应制备 1-未取代的 2-芳基
吲嗪类化合物的方法。在温和的条件下合成了几种新型 1-未取代的 2-芳基-3-乙酰基、3-苯甲酰基、3-乙氧羰基和 3-(4-
硝基苯甲酰基)
吲哚类化合物 3a-v,产率为合理到中等。