Highly Enantioselective Conjugate Additions of Potassium Organotrifluoroborates to Enones by Use of Monodentate Phosphoramidite Ligands
作者:Ate Duursma、Jean-Guy Boiteau、Laurent Lefort、Jeroen A. F. Boogers、André H. M. de Vries、Johannes G. de Vries、Adriaan J. Minnaard、Ben L. Feringa
DOI:10.1021/jo0487810
日期:2004.11.1
rhodium-catalyzed asymmetric conjugate addition of potassium organotrifluoroborates to various enones in the absence of water is described. A systematic search for effective catalysts has been performed by use of high-throughput screening methods. Initially, we have screened reaction conditions, catalyst precursors, and focused ligand libraries. In the next stage we have used the monodentate ligand combination
描述了亚磷酰胺配体在不存在水的情况下在铑催化的有机三氟硼酸钾向各种烯酮的不对称共轭加成中的使用。已经通过使用高通量筛选方法对有效催化剂进行了系统的研究。最初,我们筛选了反应条件,催化剂前体和聚焦的配体库。在下一步中,我们使用了单齿配体组合方法,最后我们通过在机器人中进行并行合成(即时配体库)建立了96种不同的亚磷酰胺的文库,并在环己烯酮的乙烯基化(高达88%对映异构体)中对其进行了测试。过量的ee)和4-苯基-3-丁烯-2-一(最高ee的42%)。通过使用苯基三氟硼酸钾对环己烯酮的丙烯酸化,得到具有99%ee的3-苯基环己酮。