937798-07-7Relevant articles and documents
Iridium-Catalyzed Asymmetric Hydrogenation of ?- A nd ?-Ketoacids for Enantioselective Synthesis of ?- A nd ?-Lactones
Hua, Yun-Yu,Bin, Huai-Yu,Wei, Tao,Cheng, Hou-An,Lin, Zu-Peng,Fu, Xing-Feng,Li, Yuan-Qiang,Xie, Jian-Hua,Yan, Pu-Cha,Zhou, Qi-Lin
, p. 818 - 822 (2020)
A highly efficient asymmetric hydrogenation of ?- A nd ?-ketoacids was developed by using a chiral spiro iridium catalyst (S)-1a, affording the optically active ?- A nd ?-hydroxy acids/lactones in high yields with excellent enantioselectivities (up to >99% ee) and turnover numbers (TON up to 100000). This protocol provides an efficient and practical method for enantioselective synthesis of Ezetimibe.
according to folds Mai Bu and its intermediate synthesis method
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Paragraph 0076; 0077; 0078; 0079; 0080; 0081, (2017/07/26)
The invention provides an Ezetimibe synthesis method comprising the following steps: (a) a compound (5) is subjected to asymmetric reduction reaction to obtain a compound (6), and the compound (6) and tert-butyldimethylsilyl chloride react in an organic solution under the action of alkali to obtain a compound (7); (b) the compound (7) and diisopropylethylamine are dissolved in the organic solution, titanium tetrachloride is added in the organic solution to react at 20-50 DEG C, and a compound (3) is added in the organic solution at minus 20 to minus 60 DEG C to react to obtain a compound (8); (c) the compound (8) and N,O-bis(trimethylsilyl) acetamide react in the organic solution at 20-80 DEG C, tetrabutylammonium fluoride trihydrate is added into the organic solution to react at 20-80 DEG C to obtain a compound (9); (d) the compound (9) is subjected to off-protection reaction to obtain Ezetimibe, wherein R is equal to TBS, Ac or COOCH2CCl3. The invention further provides an Ezetimibe intermediate and a preparation method thereof.