Efficient synthesis of halo indanones via chlorosulfonic acid mediated Friedel–Crafts cyclization of aryl propionic acids and their use in alkylation reactions
- 作者：Anil K. Sharma ; Amutha V. Subramani ; Christopher B. Gorman
- 刊名：Tetrahedron
- 出版年：2007
- 期刊代码：107_00404020
- 类别：ch
- 出版时间：8 January 2007
- 卷：63
- 期：2
- 页码：389-395
- 文件大小：531 K
摘要
Several halo indanones were synthesized from benzyl Meldrum's acid derivatives in two steps. Although several Lewis acids are effective for the Friedel–Crafts ring-closing reaction on more electron-rich arenes, in the case of the electron-deficient arenes this chemistry is not efficient. Here it is reported that chlorosulfonic acid (used as solvent) is an efficient reagent for cyclization of electron-withdrawing arenes. These molecules are potentially useful for subsequent alkylation reactions. The selective alkylation of 5,7-dibromo indanone is demonstrated using Pd-catalyzed Grignard coupling to provide monoalkylated indanone in good yield.