Hydrochloric Acid → 2-Bromopropionyl-beta-alanine-benzyl ester

HRID 399369Notes

Reaction equation

HRID 399369 reaction equation
[Br:1][CH:2]([CH3:6])[C:3](Cl)=[O:4].C1(C)C=CC(S(O)(=O)=O)=CC=1.[CH2:18]([O:25][C:26](=[O:30])[CH2:27][CH2:28][NH2:29])[C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1.C(N(CC)CC)C.Cl>C(Cl)Cl.O>[CH2:18]([O:25][C:26](=[O:30])[CH2:27][CH2:28][NH:29][C:3](=[O:4])[CH:2]([Br:1])[CH3:6])[C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1

Participants

7

Reactant 4

HCID 313Hydrochloric AcidHCID 8471TriethylamineHCID 979802-Bromopropanoyl chlorideHCID 135021004-Methylbenzene-1-sulfonic acid--benzyl beta-alaninate (1/1)

Product 1

HCID 158854972-Bromopropionyl-beta-alanine-benzyl ester

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6344DichloromethaneSolvent

Conditions

Temperature
0 °C

Procedure

53.65 g (313 mmol) of 2-bromopropionic acid chloride is added in drops at 0°C. to 100 g (285 mmol) of β-alanine-benzyl ester-p-toluenesulfonic acid salt and 31.67 g (313 mmol) of triethylamine in 400 ml of methylene chloride. The temperature is not allowed to exceed 5° C. After addition is completed, it is stirred for 1 hour at 0° C., then for 2 hours at room temperature. 500 ml of ice water is added, and the water phase is set at pH 2 with 10% aqueous hydrochloric acid. The organic phase is separated, washed once each with 300 ml of 5% aqueous hydrochloric acid, 300 ml of 5% aqueous soda solution and 400 ml of water. The organic phase is dried on magnesium sulfate and evaporated to dryness in a vacuum. The residue recrystallizes from diisopropyl ether.

Workup

  1. customto exceed 5° C
  2. additionAfter addition
  3. waitfor 2 hours at room temperature
  4. customThe organic phase is separated
  5. washwashed once each with 300 ml of 5% aqueous hydrochloric acid, 300 ml of 5% aqueous soda solution and 400 ml of water
  6. customThe organic phase is dried on magnesium sulfate
  7. customevaporated to dryness in a vacuum
  8. customThe residue recrystallizes from diisopropyl ether

Sources & evidence

ORD record
ord-a3c2808e5ec2411fb50d082556d1a491
Source dataset
uspto-grants-1998_10
Patent number
US05820849

Reaction notes

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