反应详情

温度

45 °C

Sodium hypophosphite hydrate (986 g, 11.2 mol) and Raney nickel (500 g of a 50% aqueous suspension) were added to a solution of the product from Step B (790 g, 2.8 mol) in a 2:1:1 mixture of pyridine-acetic acid-water (7 L). The mixture was stirred at 45° C. for 7 h, then cooled to 25° C. overnight and filtered through a filter-aide rinsing with water and ethyl acetate. The filtrate was washed with saturated sodium hydrogenphosphate to pH 5, water and brine, dried over sodium sulfate and concentrated. During concentration, 4 L of heptane was added to azeotropically remove pyridine. After 8 L of solvent had been removed the product solidified. Heptane (5 L) was added and the solid was triturated, isolated by filtration and vacuum dried at 35° C. to yield the desired product (722 g, 90%).

1. temperaturecooled to 25° C. overnight
2. filtrationfiltered through a filter-aide
3. washrinsing with water and ethyl acetate
4. washThe filtrate was washed with saturated sodium hydrogenphosphate to pH 5, water and brine
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated
7. concentrationDuring concentration, 4 L of heptane
8. additionwas added to azeotropically remove pyridine
9. customAfter 8 L of solvent had been removed the product
10. additionHeptane (5 L) was added
11. customthe solid was triturated
12. customisolated by filtration and vacuum
13. customdried at 35° C.