Synthesis of (R)- and (S)-3-(tert-butyldimethylsilyloxy)-1-pyrroline N-oxides — chiral nitrones for synthesis of biologically active pyrrolidine derivative, Geissman-Waiss lactone
摘要:
Tungstate-catalyzed oxidation of O-tert-butyldimethylsilyl (O-TBDMS) protected (R)-3-hydroxypyrrolidine ((R)-2), derived from trans-4-hydroxy-L-proline, gave O-TBDMS protected (R)-3-hydroxy-1-pyrroline N-oxide ((R)-1), which is a new chiral precursor for the synthesis of Geissman-Waiss lactone. The enantiomeric nitrone (S)-1 was also prepared by the oxidation of (S)-2 derived from L-malic acid. (C) 1998 Elsevier Science Ltd. All rights reserved.
Regioselective Synthesis of Nitrones by Decarboxylative Oxidation of<i>N</i>-Alkyl-<i>α</i>-amino Acids and Application to the Synthesis of 1-Azabicyclic Alkaloids
were prepared by catalytic oxidation of the corresponding chiral pyrrolidines in a regioselective manner. These chiral cyclic nitrones, 17 and 45 are versatile intermediates for the synthesis of optically active nitrogen heterocycles, since stereoselective additions of carbon nucleophiles to these chiral nitrones can be readily performed. Typically, ZnI2-mediated addition of ketene t-butyldimethylsilyl
Synthesis of (R)- and (S)-3-(tert-butyldimethylsilyloxy)-1-pyrroline N-oxides — chiral nitrones for synthesis of biologically active pyrrolidine derivative, Geissman-Waiss lactone
Tungstate-catalyzed oxidation of O-tert-butyldimethylsilyl (O-TBDMS) protected (R)-3-hydroxypyrrolidine ((R)-2), derived from trans-4-hydroxy-L-proline, gave O-TBDMS protected (R)-3-hydroxy-1-pyrroline N-oxide ((R)-1), which is a new chiral precursor for the synthesis of Geissman-Waiss lactone. The enantiomeric nitrone (S)-1 was also prepared by the oxidation of (S)-2 derived from L-malic acid. (C) 1998 Elsevier Science Ltd. All rights reserved.