Liu Wei, Chen Di, Zhu Xia-Zhen, Wan Xiao-Long, Hou Xue-Long
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai, 200032, China.
J Am Chem Soc. 2009 Jul 1;131(25):8734-5. doi: 10.1021/ja902410w.
A highly diastereo- and enantioselective cyclopropanation reaction was realized in the reaction of acyclic amides with monosubstituted allyl carbonates via Pd-catalysis using a ferrocene ligand with H as a substituent on an oxazoline ring, providing cyclopropane products having three chiral centers in yields of 67-83%, the dr ratio being 4-23:1, and ee being 83-97%. The presence of LiCl is important for the gain of high diastereo- and enantioselectivities of the reaction.
通过钯催化,使用恶唑啉环上带有H作为取代基的二茂铁配体,实现了无环酰胺与单取代碳酸烯丙酯反应中的高度非对映和对映选择性环丙烷化反应,得到了具有三个手性中心的环丙烷产物,产率为67 - 83%,非对映体比例为4 - 23:1,对映体过量为83 - 97%。LiCl的存在对于获得该反应的高非对映和对映选择性很重要。