An Efficient Synthetic Approach to
<i>trans</i>
‐(NHC)
<sub>2</sub>
Pd(R)Br Type Complexes and Their Use in Suzuki–Miyaura Cross‐Coupling Reactions
作者:Anuj Kumar、A. P. Prakasham、Manoj Kumar Gangwar、Pratap Vishnoi、Raymond J. Butcher、Prasenjit Ghosh
DOI:10.1002/ejic.201700017
日期:2017.4.10
corresponding palladium(II) precursor complexes, 2(a−b), by the reaction with the respective Grignard reagents in good to excellent yields (74−93 %). Three of the four mixed organo-halo palladium complexes 3(a1−a2) and 3b1, have been structurally characterized by the single crystal X-ray diffraction technique that revealed the trans-disposition of the NHC ligands around the palladium center. The implication
反式-(NHC)2Pd(R)Br 型混合有机卤钯配合物可通过配体取代反应从反式-(NHC)2PdBr2 型配合物方便地获得。特别地,反式-[1-(1S)-薄荷基-4-(R1)-1,2,4-三唑-5-亚基]2Pd(R2)Br[R1=Et,R2=CH2Ph(3a1);R1 = Et,R2 = o-OMeC6H4 (3a2);R1 = R2 = CH2Ph (3b1);R1 = CH2Ph, R2 = o-OMeC6H4 (3b2)] 配合物是从相应的钯 (II) 前体配合物 2(a-b) 中获得的,通过与相应的格氏试剂反应,产率良好至极好 (74-93 %)。四种混合有机卤素钯配合物 3(a1-a2) 和 3b1 中的三种已通过单晶 X 射线衍射技术进行结构表征,该技术揭示了 NHC 配体在钯中心周围的转位。