Stereoselective synthesis of 3-alkylidene/alkylazetidin-2-ones from azetidin-2,3-diones
作者:Dharmendra Kumar Tiwari、Ashif Y. Shaikh、Laxmikant S. Pavase、Vikas K. Gumaste、Abdul Rakeeb A.S. Deshmukh
DOI:10.1016/j.tet.2006.12.010
日期:2007.3
Azetidin-2,3-diones have been used as synthons for the synthesis of C-3 alkylidene/alkylazetidin-2-ones. Some of the 3-alkylazetidin-2-ones are well known for their cholesterol absorption inhibitor activity. A regio and stereoselective Grignard reaction on a keto group followed by dehydration using PPh3/CCl4 reagent is a key step in this synthesis. Hydrogenation of the 3-alkylideneazetidin-2-ones provided stereoselectively cis-3-alkylazetidin-2-ones in very good yields. (c) 2006 Published by Elsevier Ltd.