486460-00-8Relevant articles and documents
Application of the asymmetric hydrogenation of enamines to the preparation of a beta-amino acid pharmacophore
Kubryk, Michele,Hansen, Karl B.
, p. 205 - 209 (2006)
(3R)-3-[N-(tert-Butoxycarbonyl)amino]-4-(2,4,5-trifluorophenyl)butanoic acid 7a has been synthesized by an asymmetric hydrogenation of enamine ester 3 using chiral ferrocenyl ligands I and II in conjunction with [Rh(COD)Cl] 2. The direct reduction of 3 provides amino ester 1b in 93% ee, which was isolated as an (S)-camphorsulfonic acid salt to upgrade the enantiomeric excess to >99%. A more concise approach was developed involving the in situ protection of 1b using di-tert-butyldicarbonate. This approach provided the desired N-Boc amino ester 7b directly from the hydrogenation with 97% ee, which was upgraded to >99% ee upon crystallization.
Preparation method of chiral 4 - aryl - β β-amino acid derivative
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Paragraph 0056-0058, (2021/11/14)
Provided is a method for preparing a chiral 4-aryl-β-amino acid derivative. The preparation method comprises hydrogenating an enamine compound having a structure as shown in Formula III in an organic solvent in the presence of a catalyst containing a transition metal and BIBOPs. The preparation method of the present invention uses a small amount of a selected asymmetric catalyst, and has a simple operation, mild reaction conditions, a high yield, a high stereoselectivity, and better industrial application and economic values.
Preparation method of 1,3-dicarbonyl compound and intermediate of the 1,3-dicarbonyl compound
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, (2020/05/02)
The invention discloses a preparation method of a 1,3-dicarbonyl compound and an intermediate of the 1,3-dicarbonyl compound, and particularly discloses a preparation method of a compound as shown ina formula I. The preparation method comprises the following step: in a solvent, performing an elimination reaction as shown in the specification on a compound as shown in a formula II to obtain the compound as shown in the formula I, wherein R is a tert-butoxy group, a methoxy group, an ethoxy group or a methyl group. The preparation method disclosed by the invention is relatively low in cost andbeneficial to industrial production.