Synthesis of chiral 3,3′-disubstituted 1,1′-binaphthyl-2,2′-disulfonic acids |
| |
Authors: | Manabu Hatano Yoshihiro Sugiura Kazuaki Ishihara |
| |
Institution: | 1. Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8603, Japan;2. Japan Science and Technology Agency (JST), CREST, Furo-cho, Chikusa, Nagoya 464-8603, Japan |
| |
Abstract: | A convenient synthesis of chiral 3,3′-disubstituted 1,1′-binaphthyl-2,2′-disulfonic acids (BINSA, 1) was developed. The key was directed ortho-lithiation of BINSA methyl ester 2 with n-BuLi and subsequent reaction with an electrophile. Electrophiles such as Br2, I2, Me3SiOTf, and i-PrOB(Pin) reacted smoothly with 3,3′-dilithiated BINSA methyl ester, and the corresponding 3,3′-dihalo-, 3,3′-bis(trimethylsilyl)-, and 3,3′-diboryl-BINSA derivatives were obtained in yields of 21–78%. This simple synthetic method is highly attractive since the ability to prepare 3,3′-disubstituted BINOLs in advance can be useful. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|