A Short Approach to N-Aryl-1,2,3,4-tetrahydroisoquinolines from N-(2-Bromobenzyl)anilines via a Reductive Amination/Palladium-Catalyzed Ethoxyvinylation/Reductive N-Alkylation Sequence
作者:Franz Bracher、Carina Glas、Ricky Wirawan
DOI:10.1055/s-0040-1706002
日期:2021.6
Starting from readily available ortho-brominated aromatic aldehydes and primary aromatic amines, condensation of these building blocks under reductive conditions gives N-aryl 2-bromobenzylamines. The C-3/C-4-unit of the tetrahydroisoquinoline is introduced using commercially available 2-ethoxyvinyl pinacolboronate under Suzuki conditions. Finally, the obtained crude ortho-ethoxyvinyl benzylamines are cyclized
N-芳基-1,2,3,4-四氢异喹啉是通过方便且简短的方法获得的,在芳环上均具有宽范围的取代基,且官能团耐受性高。从容易获得的邻溴代芳族醛和伯芳族胺开始,这些结构单元在还原条件下的缩合得到N-芳基2-溴苄基胺。在铃木条件下,使用可商购的2-乙氧基乙烯基频哪醇硼酸酯引入四氢异喹啉的C-3 / C-4-单元。最后,使用三乙基硅烷/ TFA的组合,通过分子内的还原胺化作用,将获得的粗制邻乙氧基乙烯基苄基胺环化,得到所需的N-芳基-1,2,3,4-四氢异喹啉。