Convenient Resolution of (+/-)-Piperidine-2-carboxylic Acid ((+/-)-Pipecolic Acid) by Separation of Palladium(II) Diastereomers Containing Orthometallated (S)-(-)-1-naphthalene

Article abstract of DOI:10.1016/0957-4166(95)00400-9

(+/-)-Piperidine-2-carboxylic acid ((+/-)-pipecolic acid) has been resolved by the fractional crystallisation of diastereomeric palladium(II) complexes containing orthometallated (S)-(-)-1-<1-dimethylamino)ethyl>naphthalene.The enantiomers of the acid were liberated from the individual configurationally homogeneous diastereomers of the complex in high yield with <α>_D +/- 26.0 (c 1.00, H2O).The crystal and molecular structures of both diastereomers of the complex have been determined.