Water → Salcaprozic acid

Temperature

90 °C

A 10N sodium hydroxide solution of (4.4 mL, 44.0 mmol, 1.18 eq), 8-aminocaprylic acid (5.93 g, 37.2 mmol, 1.00 eq), sodium bicarbonate (0.88 g, 10.4 mmol, 0.28 eq) and water (5 mL) were added to a 250 mL round bottom flask equipped with a magnetic stir bar and an addition funnel. The white cloudy mixture was treated with a solution of oligosalicylate (5.20 g, 42.9 mmol 1.15 eq) and dioxane (20 mL), added over five minutes. The addition funnel was replaced with a condenser, and the reaction mixture was heated to 90 degrees C. for 3 hours (at which time the reaction was determined to have finished, by HPLC). The clear orange reaction mixture was cooled to 40 degrees C., filtered and acidified to pH=1 with 3% (by vol.) aqueous hydrochloric acid. All of the dioxane and some of the water were stripped (60 degrees C., 50 mm). The solid (which precipitated from solution during stripping) was isolated by filtration while still warm. The light pink solid was recrystallized from 50 mL of 65% ethanol-water. The solid was recovered by filtration and was dried over 18 hours in a 50 degrees C. vacuum oven. The N-(salicyloyl)-8-aminocaprylic acid was isolated as a white solid (5.35 g, 51%).

1. customequipped with a magnetic stir bar and an addition funnel
2. additionadded over five minutes
3. customThe addition funnel was replaced with a condenser
4. temperatureThe clear orange reaction mixture was cooled to 40 degrees C
5. filtration, filtered
6. custom(60 degrees C., 50 mm)
7. customThe solid (which precipitated from solution during stripping)
8. customwas isolated by filtration
9. temperaturewhile still warm
10. customThe light pink solid was recrystallized from 50 mL of 65% ethanol-water
11. filtrationThe solid was recovered by filtration
12. customwas dried over 18 hours in a 50 degrees C

ORD record

ord-704825ebc26c41bd9885ee23eceb53d7

Source dataset

uspto-grants-1999_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05962710