Benzocaine → 4-(4,5-dihydro-1,3-oxazol-2-yl)aniline

HRID 2303738Notes

Reaction equation

HRID 2303738 reaction equation
[NH2:1][C:2]1[CH:12]=[CH:11][C:5]([C:6]([O:8][CH2:9][CH3:10])=O)=[CH:4][CH:3]=1.CC([NH2:18])(C)CO.C1(C)C(C)=CC=CC=1.[NH2-].[Li+]>>[NH2:1][C:2]1[CH:12]=[CH:11][C:5]([C:6]2[O:8][CH2:9][CH2:10][N:18]=2)=[CH:4][CH:3]=1

Participants

5

Procedure

Ethyl p-aminobenzoate, 20.65 g (0.125 mol), 2-methyl-2-aminopropanol, 22.3 g (0.25 mol) 150 ml of xylene, and 0.25 g of lithium amide were combined and heated at the reflux temperature for 50 hr. The alcohol and water liberated was collected in a Dean-Stark trap, providing indication when the reaction was complete. The xylene solvent was removed and the viscous liquid was added to water to precipitate the product. After drying, a 15.5 g (65%) yield of the 4,4-dimethyl derivative of 4-aminophenyl oxazoline was obtained. The product was recrystallized from ethyl acetate, giving white, crystalline material with mp 172° C. FT-IR, with peaks centered at 3445 (NH), 1635 (—C═N—), and 1602 (phenyl) cm−1 confirmed the desired amino functionalized oxazoline. Following the Example 6 procedure, TDO was used to covert the aforesaid compound to the desired acetoacetamide. The structure of this new composition is as follows:

Workup

  1. temperatureheated at the reflux temperature for 50 hr
  2. customThe alcohol and water liberated was collected in a Dean-Stark trap
  3. customproviding indication when the reaction
  4. customThe xylene solvent was removed
  5. additionthe viscous liquid was added to water
  6. customto precipitate the product
  7. customAfter drying

Sources & evidence

ORD record
ord-e835812b6ae0448ba90776bda7bd045e
Source dataset
uspto-grants-2002_08
Patent number
US06433116B1

Reaction notes

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