CuI-Catalyzed Coupling Reaction of β-Amino Acids or Esters with Aryl Halides at Temperature Lower Than That Employed in the Normal Ullmann Reaction. Facile Synthesis of SB-214857
作者:Dawei Ma、Chengfeng Xia
DOI:10.1021/ol016258r
日期:2001.8.9
CuI-catalyzed coupling reaction of aryl halides with beta-amino acids or beta-amino esters is completed at 100 degrees C in 48 h, which indicates that the structure of the beta-amino acid has an accelerating effect for the Ullmann-type arylamination reaction. This coupling reaction can be used to prepare enantiopure N-aryl beta-amino acids. An efficient syntheticroute to SB214857, a potent GPIIb/IIIa
Chiral oxazolidines obtained by condensation of aldehydes with (-).(R)- or (+).(S)-N-benzylphenylglycinol react with the Reformatsky reagent derived from ethylbromoacetate, in mild reaction conditions (Et2O or CH2Cl2, 0°C, 15-60 min), leading to ethyl β-amino carboxylates in moderate to good diastereomeric excess (60-92%). These ring opening products are transformed into primary β-aminoesters, in
exhibited activity toward bulky β-keto esters. Furthermore, a substrate-dependent shift in enantio-preference of HBV variant towards β-keto esters with linear or branched aliphatic substituents was observed. The best variant was applied to the asymmetric synthesis of aliphatic β-amino acids at semi-preparative scale with high yield and enantioselectivity. This study will improve the general understanding
Verfahren zur Herstellung von optisch aktiven 3-Aminocarbonsäure (estern)
申请人:LONZA AG
公开号:EP0144980A2
公开(公告)日:1985-06-19
Optisch Aktive 3-Aminocarbonsäureester sowie die freien, optisch aktiven 3-Aminocarbonsäuren werden, ausgehend von β-Ketosäureestern und chiralen Aminen über die Diastereomertrennung von N-substituierten Aminosäureesterhydrochloriden hergestellt.