STUDIES ON SUZUKI COUPLING REACTIONS OF LARGE STERICALLY HINDERED SUBSTRATES

Jian Sun, Zhaohui Jin, Ning Xie, Hong Wang, Huajing Gao

ABSTRACT: Suzuki coupling reaction of 2-(Trifluormethoxy) phenylboronic acid with 2-bromo-1,3-dichloro-5-nitrobenzene were successfully conducted by using Pd2(dba)3 as the catalyst and in satisfactory to good yields. The 4-(2-(diphenylphosphino)phenyl) morpholine was the best ligand in this reaction. Biaryl amides 8t which gained much attention in the pharmaceutical industry because of using as RORγt inhibitors could be synthesized using the product of Suzuki reaction 3a as the substrate after 2 steps. Higher yield of 8t could be got by using this method than the previous work.

Keywords:Pd catalyst, Suzuki coupling reaction, hindered