Ethanolamine → tert-butyl N-(2-hydroxyethyl)carbamate

HRID 547298Notes

Reaction equation

HRID 547298 reaction equation
[OH-].[Na+].[CH2:3]([CH2:5][NH2:6])[OH:4].[C:7](OC([O-])=O)([O:9][C:10]([CH3:13])([CH3:12])[CH3:11])=[O:8].S(=O)(=O)(O)O>O1CCCC1.[Cl-].[Na+].O>[OH:4][CH2:3][CH2:5][NH:6][C:7](=[O:8])[O:9][C:10]([CH3:13])([CH3:12])[CH3:11]

Participants

7

Reactant 4

HCID 700EthanolamineHCID 1118Sulfuric AcidHCID 14798Sodium HydroxideHCID 22064466Tert-butyldicarbonate

Product 1

HCID 2733206tert-butyl N-(2-hydroxyethyl)carbamateYield 99.8%

Reagents, catalysts & solvents 2

HCID 8028TetrahydrofuranSolvent2×HCID 57417360Sodium chloride; waterSolvent

Procedure

Sodium hydroxide (800 mL of 2M in water) was added to a solution of ethanol amine (100 6, 1.64 mole) in tetrahydrofuran (850 mL). The reaction mixture was placed in a 25° C. water bath and stirred rapidly. A solution of tert-butyl dicarbonate (358 g, 1.64 mole) in tetrahydrofuran (800 mL) was added dropwise over a period of 1 hour. The reaction mixture was stirred for a total of 4 hours at which time analysis by TLC indicated that all of the starting material had been consumed. The tetrahydrofuran was removed under reduced pressure to provide an aqueous slurry. The slurry was cooled in an ice bath. The pH was adjusted to pH 2 by the addition of sulfuric acid (1 L of 1M in water). The resulting solution was extracted with ethyl acetate (4×500 mL). The combined extracts were washed sequentially with water (3×500 mL) and brine (2×500 mL), dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to give a first lot of crude product. Analysis of the aqueous and brine washes indicated that they contained product so they were extracted with ethyl acetate. The combined extracts were dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to provide a second lot of crude product. The two lots were combined to provide 263.8 g of tert-butyl (2-hydroxyethyl)carbamate as a colorless oil.

Workup

  1. customwas placed in a 25° C.
  2. stirringThe reaction mixture was stirred for a total of 4 hours at which time analysis by TLC
  3. customhad been consumed
  4. customThe tetrahydrofuran was removed under reduced pressure
  5. customto provide an aqueous slurry
  6. temperatureThe slurry was cooled in an ice bath
  7. extractionThe resulting solution was extracted with ethyl acetate (4×500 mL)
  8. washThe combined extracts were washed sequentially with water (3×500 mL) and brine (2×500 mL)
  9. dry with materialdried over anhydrous sodium sulfate
  10. filtrationfiltered
  11. concentrationconcentrated under reduced pressure
  12. customto give a first lot of crude product
  13. extractionwere extracted with ethyl acetate
  14. dry with materialThe combined extracts were dried over anhydrous sodium sulfate
  15. filtrationfiltered
  16. concentrationconcentrated under reduced pressure
  17. customto provide a second lot of crude product

Sources & evidence

ORD record
ord-44c96a0a84c4412f937c8c3ad531ba96
Source dataset
uspto-grants-2011_05
Patent number
US07939526B2

Reaction notes

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