Catalytic intramolecular hydroamination of aminoallenes using titanium complexes of chiral, tridentate, dianionic imine-diol ligands
作者:Fanrui Sha、Benjamin S. Mitchell、Christopher Z. Ye、Chase S. Abelson、Eric W. Reinheimer、Pierre LeMagueres、Joseph D. Ferrara、Michael K. Takase、Adam R. Johnson
DOI:10.1039/c8dt05156a
日期:——
confirmed retention of stereochemistry during synthesis. X-ray crystal structures of four of the ligands show either inter- or intramolecular hydrogen bonding interactions. The ligands coordinate to the titanium reagents Ti(NMe2)4 or TiCl(NMe2)3 by protonolysis and displacement of two equivalents of HNMe2. The crystal structure of one example of Ti(X2L)Cl(NMe2) was determined and the complex has a distorted
的烷基化d -或大号-苯丙氨酸或缬氨酸的烷基酯进行了使用甲基或苯基格氏试剂。随后与水杨醛,3,5-二叔丁基水杨醛或5-氟水杨醛缩合形成X 2 L型Schiff碱配体。手性位移NMR证实了合成过程中立体化学的保留。四个配体的X射线晶体结构显示分子间或分子内氢键相互作用。配体通过质子分解和置换两个当量的HNMe 2与钛试剂Ti(NMe 2)4或TiCl(NMe 2)3配位。。确定了Ti(X 2 L)Cl(NMe 2)的一个实例的晶体结构,并且该络合物具有带有轴向NMe 2配体的扭曲的方形锥体形状。双-二甲基酰胺配合物是用于二和三取代的氨基丙烯的闭环加氢胺化的活性催化剂。庚4,5-二烯胺在135°C下与5 mol%的催化剂反应,得到6-乙基-2,3,4,5-四氢吡啶(40-72%)以及Z-和E -2的混合物-丙烯基吡咯烷(25–52%)。6-甲基-庚基-4,5-二烯基胺在135°C下与5 mol