Acetic Anhydride → N-isopropyl-4'-hydroxy-acetanilide

Temperature

50 °C

Ten g (0.066 moles) of N-isopropyl-p-hydroxyaniline was dissolved in 50 ml acetic acid and to this mixture was added 13.5 g (0.132 moles) of acetic anhydride. This reaction was heated to 50° C. for 5 hours, then poured over crushed ice. Sodium carbonate was added until the pH was approximately 8.5, then the solution was extracted with chloroform, dried over anhydrous magnesium sulfate, and evaporated to dryness giving an oil which immediately was placed into 10% sodium hydroxide and warmed to 70° C. for 5 hours. Upon cooling, the mixture was extracted with chloroform, then made acidic with 10% HCl until the pH of the solution was 2-3. The solution was then extracted with chloroform, dried over anhydrous magnesium sulfate, and evaporated to dryness giving 7.6 g (60%) of N-isopropyl-4'-hydroxy-acetanilide as a white solid that was recrystallized from water, m.p. 152°-153° C. I.R. 3300-3200 cm-1 (--OH) and 1660 cm-1 (amide carbonyl). The sodium salt of this compound was prepared by reacting an equal molar quantity thereof with sodium hydroxide in water. The water was evaporated to dryness leaving the sodium salt as a solid which was dried further, m.p. 52°-54° C.

1. additionpoured
2. customover crushed ice
3. extractionthe solution was extracted with chloroform
4. dry with materialdried over anhydrous magnesium sulfate
5. customevaporated to dryness
6. customgiving an oil which
7. temperaturewarmed to 70° C. for 5 hours
8. temperatureUpon cooling
9. extractionthe mixture was extracted with chloroform
10. extractionThe solution was then extracted with chloroform
11. dry with materialdried over anhydrous magnesium sulfate
12. customevaporated to dryness

ORD record

ord-639624de7d634b4bae4fd6412dc5c40b

Source dataset

uspto-grants-1985_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04520134