Preparation background and overview of (+)-N,N’-(1S,2S)-1,2-diaminocyclohexanebis(2-pyridinecarboxamide)
(+)-N,N’-(1S,2S)-1,2-diaminocyclohexanebis(2-pyridinecarboxamidefluoroborate) can be used as a pharmaceutical and chemical synthesis intermediate. If (+)-N,N’-(1S,2S)-1,2-diaminocyclohexanebis(2-pyridinecarboxamide) is inhaled, move patient to fresh air; if skin contact occurs, remove Wear decontaminated clothes, rinse your skin thoroughly with soap and water, and seek medical attention if you feel unwell. If your eyes come into contact with your eyes, separate your eyelids, rinse them with running water or saline, and seek medical attention immediately. If ingested, rinse your mouth immediately. It is forbidden to induce vomiting and seek medical attention immediately.
Preparation of (+)-N,N’-(1S,2S)-1,2-diaminocyclohexane bis(2-pyridinecarboxamide)
Add 1,1′-carbonyldiimidazole (1.7Kg, 10.48mol) and THF (7.5L) into a 22L flask, add solid picolinic acid (1.36Kg, 11mol) to the slurry at room temperature, and react The mixture was cooled endothermically from 18°C to 12°C and then the reaction mixture was heated to 18-19°C. The resulting clear solution was stirred for 1 hour and (1S,2S)-dimethylsulfoxide(+)-1,2-diaminocyclohexane (0.5Kg, 4.38mol) was added over 1 hour while maintaining the temperature below 50°C, rinse the beaker and funnel with 2.5L THF, stir the reaction at room temperature for 15 hours, add water (0.5L) to the thin slurry to obtain a clear solution, stir the reaction mixture for 1 hour, evaporate the reaction mixture by rotary evaporation Concentrated to an orange semi-solid, the reaction product was slurried in 5L ethanol and concentrated by rotary evaporation. Dissolved in ethanol (5L) at 64-65°C, cooled, the solution became turbid at around 58°C. The turbid solution was inoculated (10 g) at this temperature and cooled to -8 °C. The resulting white crystals were isolated by filtration on a sintered glass funnel and washed with 5 L of cold water. ethanol (-8 to -10°C), purged with nitrogen under room vacuum, and dried in a vacuum oven (35°C). This resulted in the isolation of 1.23 Kg (86.3%) of white crystalline solid.