Brown Laboratories, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware, 19716, United States.
J Org Chem. 2012 Nov 2;77(21):9900-4. doi: 10.1021/jo3019076. Epub 2012 Oct 19.
Described is a Cu-catalyzed directed carbozincation of cyclopropenes with organozinc reagents prepared by I/Mg/Zn exchange. This protocol broadens the scope with respect to functional group tolerance and enables use of aryl iodide precursors, rather than purified diorganozinc precursors. Critical to diastereoselectivity of the carbozincation step is the removal of magnesium halide salts after transmetalation with ZnCl(2).
描述了一种铜催化的环丙烯与通过 I/Mg/Zn 交换制备的有机锌试剂的导向碳锌化反应。该方案扩大了官能团耐受性的范围,并允许使用芳基碘化物前体,而不是纯化的二有机锌前体。碳锌化步骤的非对映选择性的关键是在与 ZnCl2进行转金属化后除去卤化镁盐。