Asymmetric Mannich Reactions of β-Keto Esters with Acyl Imines Catalyzed by Cinchona Alkaloids
作者:Sha Lou、Brandon M. Taoka、Amal Ting、Scott E. Schaus
DOI:10.1021/ja0537373
日期:2005.8.1
Cinchona alkaloids catalyze the enantioselective Mannich reaction of beta-keto esters with acyl aryl imines. The reaction requires 10 mol % of cinchonine or cinchonidine. The reaction products are obtained in good yields (81-99%), high enantioselectivities (80-96% ee), and in diastereoselectivities that range from 1:1 to >95:5. The cinchonine-catalyzed reaction provides access to highly functionalized
Enzymatic Synthesis of Enantiomerically Pure β-Amino Ketones, β-Amino Esters, and β-Amino Alcohols with Baeyer-Villiger Monooxygenases
作者:Jessica Rehdorf、Marko D. Mihovilovic、Marco W. Fraaije、Uwe T. Bornscheuer
DOI:10.1002/chem.201001480
日期:2010.8.16
The enzymatic kinetic resolution of a broad set of β‐amino ketones was investigated by using a collection of 16 Baeyer–Villigermonooxygenases from different bacterial origins, which display various substrate specificities. Within this platform of enzymes excellent enantioselectivities (E>200) were found towards aliphatic and aromatic 4‐amino‐2‐ketones, and some enzymes even showed opposite enantioselectivity