Foley & Lardner LLP
Process for preparation of N-Boc biphenyl alaninol
A process is provided for preparation of (R)-N-Boc biphenyl alaninol. It provides a preparation process for a compound outlined as compound 4, which includes these operations: in one of the alcohol solvents, asymmetric hydrogenation of 5 in the presence of [Rh(Duanphos)(X)]Y and hydrogen to provide compound 4. Here “Duanphos” is (Rc,Sp)-Duanphos or (Sc,Rp)-Duanphos; X is NBD or/and COD; Y is one or more of BF4, PF6, SbF6. This process has a lot of advantages, such as low cost, safe operation, less pollution and high yield. The product was obtained in >99% purity and ee which is suitable to scale up in industrial scale.
JIANGXI LONG LIFE BIO-PHARMACEUTICAL CO., LTD. CHIRAL QUEST (SUZHOU) CO., LTD.
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inventional inventional inventional inventional
Siming Yi Hongfeng Lei Yongxiang Shengwen Wenge Tengyue Li
Hu Tao Liu Wu Chi Wu Li Xu Zou