A Facile Synthesis of Vicinal Diamines Promoted by Low-Valent Niobium: Preparation of Chiral Octahydrobiisoquinolines and Their Application to Catalytic Asymmetric Synthesis
作者:Shigeru Arai、Satoshi Takita、Atsushi Nishida
DOI:10.1002/ejoc.200500301
日期:2005.12
homocoupling of imines to give vicinal diamines promoted by low-valent niobium, generated by treatment of NbCl5 with zinc powder, is described. The desired products were obtained in good to excellent yields. Dihydroisoquinoline derivatives also gave the coupling products with good diastereoselectivities (D,L/meso). Optical resolution of the racemic octahydrobiisoquinolines was achieved and their complexes
描述了通过用锌粉处理 NbCl5 产生的低价铌促进亚胺的有效均偶联以产生邻二胺。以良好至极好的收率获得了所需产物。二氢异喹啉衍生物也产生具有良好非对映选择性(D,L/meso)的偶联产物。实现了外消旋八氢双异喹啉的光学拆分,并将它们与 CuI 的配合物用于 β-萘酚的催化不对称氧化偶联。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)