Doyle Michael P, Hu Wenhao, Valenzuela Marcela V
Department of Chemistry, University of Arizona, Tucson, Arizona 85721, USA.
J Org Chem. 2002 May 3;67(9):2954-9. doi: 10.1021/jo016220s.
The total synthesis of (S)-(+)-imperanene, a natural product found in Chinese medicine, has been completed in 12 steps from a commercially available cinnamic acid. The key step is highly enantioselective carbon-hydrogen insertion from a diazoacetate using a chiral dirhodium(II) carboxamidate catalyst. An elimination process essential to the construction has been optimized to avoid intramolecular Friedel-Crafts alkylation.
从市售肉桂酸出发，经12步完成了中药中发现的天然产物（S）-（+）-紫穗槐烯的全合成。关键步骤是使用手性二铑（II）羧酰胺催化剂，由重氮乙酸酯进行高度对映选择性的碳-氢插入反应。对构建过程中必不可少的消除过程进行了优化，以避免分子内傅克烷基化反应。
