过渡金属催化的炔丙基亲电子试剂和格氏试剂的交叉偶联提供了高度官能化的产物,是极其有用的合成中间体。然而,由于具有挑战性的区域选择性,将炔丙基衍生物转化为炔丙基化合物的例子仍然有限。我们使用LaCl 3 ·2LiCl在没有配体的情况下催化格氏试剂的炔丙基化,具有高区域选择性和立体特异性。该方法显示了使用烷基或(杂)芳基格氏试剂和具有不同离去基团的炔基亲电子试剂的广泛底物范围。我们的方案进一步应用于叶毛多辛 B 的正式合成。利用天然丰富且相对无毒的镧催化剂的方法值得探索。
Multimetallic Ir–Sn3-catalyzed substitution reaction of π-activated alcohols with carbon and heteroatom nucleophiles
作者:Arnab Kumar Maity、Paresh Nath Chatterjee、Sujit Roy
DOI:10.1016/j.tet.2012.10.086
日期:2013.1
An atom economic and catalytic substitutionreaction of π-activated alcohols by a multimetallic Ir–Sn3 complex has been demonstrated. The multimetallic Ir–Sn3 complex can be easily synthesized from the reaction between [Cp∗IrCl2]2 and SnCl2. In presence of as little as 1 mol % of the catalyst three different types of π-activated alcohols, namely benzyl, allyl, and propargyl alcohols, have been successfully