N,N′-Dibenzosuberyl-1,1′-Binaphthyl-2,2′-diamine: A Highly Effective Supporting Ligand for the Enantioselective Cyclization of Aminoalkenes Catalyzed by Chelating Diamide Complexes of La(III) and Y(III)
作者:Tom Livinghouse、Khoi Huynh、Helena Lovick
DOI:10.1055/s-0033-1340186
日期:——
Enantioselective hydroamination/cyclization of representative aminoalkenes catalyzed by chelating diamide complexes of La(III) and Y(III) are described. It is noteworthy that the La(III) complex derived from the sterically demanding ( R )- N , N ′-dibenzosuberyl-1,1′-binaphthyl-2,2′-diamine proligand provides enantioselectivities that are in many cases significantly higher than those obtained with
描述了由螯合 La(III) 和 Y(III) 的二酰胺配合物催化的代表性氨基烯烃的对映选择性加氢胺化/环化。值得注意的是,由空间要求高的 (R)-N , N '-dibenzosuberyl-1,1'-binaphthyl-2,2'-diamine proligand 衍生的 La(III) 配合物提供的对映选择性在许多情况下显着高于那些用相应的 Y(III) 类似物获得的。此外,与 La(III) 对应物相比,LiCl 的存在通常会抑制 Y(III) 配合物获得的速率和对映选择性,此外还完全抑制 7b 的双环化。后一项研究中使用的酰胺配合物是通过使用新的高活性碱 La[N(TMS)(t-Bu)] 3 和 Y[N(TMS)( t-Bu)] 3 通过“胺消除”制备的。