LEWIS-ACID-MEDIATED AND CATIONIC LITHIUM-MEDIATED DIASTEREOSELECTIVE ALDOL-TYPE REACTION-BASED ON A DOUBLE CHIRAL RECOGNITION MANNER FOR THE ASYMMETRIC-SYNTHESIS OF ALPHA-SUBSTITUTED SERINES

Authors
SANO S LIU XK TAKEBAYASHI M KOBAYASHI Y TABATA K SHIRO M NAGAO Y
Citation
S. Sano et al., LEWIS-ACID-MEDIATED AND CATIONIC LITHIUM-MEDIATED DIASTEREOSELECTIVE ALDOL-TYPE REACTION-BASED ON A DOUBLE CHIRAL RECOGNITION MANNER FOR THE ASYMMETRIC-SYNTHESIS OF ALPHA-SUBSTITUTED SERINES, Tetrahedron letters, 36(23), 1995, pp. 4101-4104
Citations number
12
Categorie Soggetti
Chemistry Inorganic & Nuclear
Journal title
Tetrahedron letters → ACNP
ISSN journal
00404039
Volume
36
Issue
23
Year of publication
1995
Pages
4101 - 4104
Database
ISI
SICI code
0040-4039(1995)36:23<4101:LACLDA>2.0.ZU;2-R
Abstract
Diastereoselective aldol-type reaction of ethyl (5R or hoxy-2,5-dihydr o-5-isopropyl-2-pyrazinecarboxylate (5) with chiral aldehyde 7 was inv estigated by using Sn(OSO2CF3)(2)-N-ethylpiperizine, MgBr2-Et(3)N, n-b utyllithium, and lithium diisopropylamide. The mediation mode with Sn( II) between (5R or 5S)-5 and 7 proved to be quite different from that with Mg(II). The two aldol products were converted to the correspondin g gamma-lactonic alpha-substituted serines (2S)- and (2R)-10.