The Synthesis and Resolution of 2,2‘-, 4,4‘-, and 6,6‘-Substituted Chiral Biphenyl Derivatives for Application in the Preparation of Chiral Materials
作者:Pedro J. Montoya-Pelaez、Yoon-Seo Uh、Christopher Lata、Matthew P. Thompson、Robert P. Lemieux、Cathleen M. Crudden
DOI:10.1021/jo060553d
日期:2006.8.1
Various routes were examined for the synthesis of chiral biphenyl species that are substituted at the 2,2‘, 4,4‘ and 6,6‘ positions. Because the biaryl bond is tetrasubstituted, many coupling reactions were not suitable. The most reliable coupling reaction proved to be the Ullmann, which gave the desired product in 82% yield. The products were required as the starting point for the preparation of chiral
检查了在2,2',4,4'和6,6'位置被取代的手性联苯物质的合成的各种途径。因为联芳基键是四取代的,所以许多偶联反应都不适合。事实证明,最可靠的偶联反应是Ullmann,以82%的收率得到所需的产物。需要使用这些产物作为使用它们作为单体制备手性材料的起点。因此,需要产生大量两种对映体的途径。通过使用手性HPLC,在倒数第二步拆分了两种对映异构体。事实证明,一个复杂的特征是必须在4,4'位具有一个反应性基团,尽管如此,这仍将允许聚合反应。最终,我们在二溴代芳烃上采用了Ullmann偶联剂,