2-氫茚1,3-二酮和2,3-丁二酸乙酯之磷催化[3+2]環化反應

Abstract

本論文以磷催化進行[3+2]環化反應，得到具位向選擇性的螺五員環衍生物。1,3-氫茚二酮是重要官能基，其衍生分子具有生物活性。將1,3-氫茚二酮與芳香醛，進行domino Knoevenagel condensation，得到2-芳香亞甲基-1,3-氫茚二酮，作為探討反應的起始物。在室溫、氮氣環境下，2-芳香亞甲基-1,3-氫茚二酮與2,3-丁二酸乙酯溶於甲苯，以三苯基膦為催化劑，進行[3+2]環化反應，得到螺五員環。不論是拉電子基或是缺電子基的起始物，得到的產物都具有良好的位向選擇性（可達5:1），並有63-99%的產率。據我們所知，這是第一個發表運用2-芳香亞甲基-1,3-氫茚二酮和2,3-丁二酸乙酯合成官能化五員環。

Using phosphine catalyzed [3+2] annulation to obtain functionalized spirocyclic cyclopentenes which has regioselectivity. 1,3-indandione is an important constituent functional group of natural product. And some derived molecules have biological activity. 2-arylidene-1,3-indandione can be obtained by domino Knoevenagel condensation of 1,3-indandione and aromatic aldehyde in a single one-pot operation. At room temperature and under nitrogen atmosphere, 2-arylidene-1,3-indandione with ethyl-2,3-butadienoate dissolved in toluene, and catalyzed by triphenylphosphine, then doing [3+2] annulation. The starting materials are either electron-donating or electron-withdrawing group, the products both have good regioselectivity (up to 5:1) and yields (63-99%). To the best of our knowledge this is the first report for the synthesis of functionalized cyclopentenes using 2-arylidene-1,3-indandione and ethyl-2,3-butadienoate.