Lewis acid-promoted direct substitution of 4-methoxy- and 4-phenylthio-2-oxazolidinones by alkyl cuprates. Facile preparation of (3s,4s)-statine and (3s,4s)-cyclohexylstatine.
摘要:
Treatment of 4-methoxy- and 4-phenylthio-2-oxazolidinones with a combination of cuprates and BF3 results in smooth formation of 4-alkyl and 4-aryl derivatives in high yield. By this method, the titled compounds of biological interest are readily synthesized from (4S,5S)-5-allyl-4-methoxy (or 4-phenylthio)-2-oxazolidinones stereoselectively.
promising method for the versatile synthesis of chiral 2-amino alcohols is provided by the enantioselective functionalization of the olefinic moiety of the simple heterocycle, 2-oxazolone, involving a stereodefined introduction of easily replaceable groups followed by stepwise substitution. Versatility of this method is shown in chiral synthesis of unusual hydroxy amino acids such as statine and hydroxyglutamic
Methoxyselenylation and methoxybromination of chiral 3-acyl-2-oxazolones with PhSeCl/MeOH and Br2/MeC(OMe)3 smoothly proceed to result in highly stereoselective formation of chiral synthons for β-aminoalcohols, but with opposite π-facial selectivity.