反应详情

温度

-15 °C

4-(4-Methoxyphenyl) butyric acid (1) (450 g, 2.32 mole) was combined with dry THF (4 L) and 4-methylmorpholine (268 mL, 2.43 mole) in a 12 L three neck flask with mechanical stirring, an ice-methanol cooling bath and nitrogen atmosphere. Small pieces of dry ice were used to bring the bath temperature below −20° C. Isobutyl chloroformate was added at a rate so as not to exceed an internal temperature of −10° C. After stirring for 30 min. at −10 to −20° C., a 4.7 M solution of ammonia in methanol (990 mL, 4.64 mole) was added in one portion. During the addition, the reaction temperature rose to 0° C. The reaction was allowed to stir for 30 min. and then allowed to stand overnight. The product mixture was transferred to a 22 L separatory funnel with ethyl acetate (6 L), and 10% sodium chloride solution (1.5 L). The layers were separated and the organic solution was washed with 10% sodium chloride solution (4×1 L) and then brine (3×500 mL). The organic layer was dried over sodium sulfate, filtered, evaporated and placed under high vacuum overnight. This afforded 432 g (97%) of the pure amide (117) as an off white solid.

1. customthe bath temperature below −20° C
2. customan internal temperature of −10° C
3. additionDuring the addition
4. customrose to 0° C
5. stirringto stir for 30 min.
6. waitto stand overnight
7. customThe layers were separated
8. washthe organic solution was washed with 10% sodium chloride solution (4×1 L)
9. dry with materialThe organic layer was dried over sodium sulfate
10. filtrationfiltered
11. customevaporated
12. customplaced under high vacuum overnight