Chlorination of enantiomerically pure 1,1′-bis(hydroxyalkyl)-3,3′-biindolizines: conservation of chirality by thermal treatment

Abstract

Enantiomerically pure 1,1′-bis(hydroxyalkyl)-3,3′-biindolizines 1 racemize unexpectedly by reaction with tetra-chloromethane–triphenylphosphine at room temperature affording the corresponding dichloro compounds 2, whereas the chirality is preserved at higher reaction temperatures.

References

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