SYNTHESIS AND CONFIGURATION OF DIASTEREOMERIC 2,4-, 2,5-, AND 2,6-PIPERIDINEDICARBOXYLIC ACIDS AND THEIR DIMETHYL ESTERS

Article abstract of DOI:10.1007/BF00506672

The reduction in an acidic medium over a platinum catalysts of 2,4-, 2,5-, and 2,6-pyridinedicarboxylic acids gave cis-2,4-, -2,5-, and -2,6-piperidinedicarboxylic acids, heating of which in an alkaline medium led to thermodynamically equilibrium mixtures of diastereomers.Individual trans-2,5-piperidinecarboxylic acid was isolated.The configurations of the 2,4-, 2,5-, and 2,6-piperidinedicarboxylic acids and their methyl esters were established by means of the PMR spectra.