A convenient access to (3S)-3-(triisopropylsilyl)oxy-1-pyrroline N- oxide, a useful intermediate for polyfunctionalized enantiopure indolizidine and pyrrolizidine synthesis

Article abstract of DOI:10.1016/S0040-4039(99)00310-X

Optimization of a strategy providing the enantiomerically pure nitrone 2 in five steps and 28% overall yield from L-malic acid has been achieved by the combined use of DIBAL-H as the reductant and triisopropylsilyl as the protecting group. The utility of nitrone 2 as synthetic intermediate is demonstrated by a ready access to polyhydroxylated indolizidines and pyrrolizidines via stereoselective 1,3-dipolar cycloaddition reactions.