Synthesis
General procedure for the synthesis of L-octahydroindole-2-carboxylic acid from the compound (CAS: 539820-41-2): 200 g of the compound obtained in the previous step was dissolved in acetic acid, followed by the addition of 5 g of 10% Pt/C catalyst to the hydrogenator. The hydrogenation reaction was carried out at room temperature and 5 bar hydrogen pressure until a theoretical amount of hydrogen was absorbed. Upon completion of the reaction, the catalyst was removed by filtration and the resulting solid product was collected by filtration after the reaction solution was cooled to 0 to 5 °C. The reaction was carried out at room temperature and 5 bar hydrogen pressure. The filter cake was washed with a suitable solvent and dried under constant weight conditions. The final product was (2S,3aS,7aS)-octahydroindole-2-carboxylic acid in 87% yield and 99% enantiomeric purity.
