Diastereoselective magnesium halide-catalyzed anti-aldol reactions of chiral N-acyloxazolidinones.
A chiral auxilliary-based direct aldol reaction is reported. The reactions are catalytic in magnesium salts and are facilitated by silylation with chlorotrimethylsilane. The adducts isolated are in high diastereoselectivity (up to 32:1 dr) and favor the anti-aldol diastereomer B. Reactions are operationally simple and can be run under ambient atmosphere without rigorous exclusion of water. Many of the adducts are highly crystalline and a single diastereomer can be isolated without chromatography.
Evans
David A
DA
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
Tedrow
Jason S
JS
Shaw
Jared T
JT
Downey
C Wade
CW
D001547:Benzaldehydes / Q000737:chemistry; D002384:Catalysis; D015636:Magnesium Chloride / Q000737:chemistry*; D023303:Oxazolidinones / Q000737:chemistry*; D013237:Stereoisomerism
D001547:Benzaldehydes; D023303:Oxazolidinones; D015636:Magnesium Chloride; C032175:benzaldehyde