Highly efficient synthesis of chiral beta-amino acid derivatives via asymmetric hydrogenation.
نویسندگان
چکیده
The Rh-TangPhos complex is an efficient hydrogenation catalyst for making chiral beta-amino acid derivatives. With the Rh-TangPhos system, high enantioselectivities (up to 99.6%) and turnover numbers have been obtained in the hydrogenation of E/Z isomeric mixtures of both beta-alkyl and beta-aryl beta-(acylamino)acrylates. [reaction: see text]
منابع مشابه
Highly efficient synthesis of beta-amino acid derivatives via asymmetric hydrogenation of unprotected enamines.
A direct asymmetric hydrogenation of unprotected enamino esters and amides is described. Catalyzed by Rh complexes with Josiphos-type chiral ligands, this method gives beta-amino esters and amides in high yield and high ee (93-97% ee). No acyl protection/deprotection is required.
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ورودعنوان ژورنال:
- Organic letters
دوره 4 23 شماره
صفحات -
تاریخ انتشار 2002