Sodium borohydride → N-[(1R)-2-hydroxy-1-(3-thienylmethyl)ethyl]acetamide

HRID 47715Notes

Reaction equation

HRID 47715 reaction equation
[C:1]([NH:4][C@H:5]([CH2:11][C:12]1[CH:16]=[CH:15][S:14][CH:13]=1)[C:6](OCC)=[O:7])(=[O:3])[CH3:2].[BH4-].[Na+]>C(O)C.O>[OH:7][CH2:6][C@H:5]([NH:4][C:1](=[O:3])[CH3:2])[CH2:11][C:12]1[CH:16]=[CH:15][S:14][CH:13]=1

Participants

5

Reactant 2

HCID 4311764Sodium borohydride2×HCID 86584423ethyl (2R)-2-(acetylamino)-3-(3-thienyl)propanoate

Product 1

HCID 69698694N-[(1R)-2-hydroxy-1-(3-thienylmethyl)ethyl]acetamideYield 78.9%

Reagents, catalysts & solvents 2

HCID 702EthanolSolventHCID 962WaterSolvent

Procedure

A solution of 2.15 g of ethyl (2R)-2-(acetylamino)-3-(3-thienyl)propanoate in 24 cm3 of ethanol, stirred under an inert atmosphere, is brought to a temperature of 20° C. 0.5 g of sodium borohydride is added and the reaction medium, which is slightly brown, is stirred for 24 hours at room temperature. A further 0.2 g of sodium borohydride is added and stirring is continued for 24 hours. After evaporation of the reaction mixture under reduced pressure (2 kPa) at a temperature in the region of 40° C., a solid residue is obtained, which is taken up in 30 cm3 of water. This mixture is extracted with twice 100 cm3 of ethyl acetate and the organic phase is then dried over magnesium sulfate and evaporated under reduced pressure (2 kPa) at a temperature in the region of 40° C. to give an off-white solid which is dried in an oven under vacuum (10 Pa) at a temperature in the region of 48° C. 1.4 g of N-[(1R)-2-hydroxy-1-(3-thienylmethyl)ethyl]acetamide are obtained in the form of an off-white solid melting at about 105° C. to become pasty. 1H NMR spectrum (400 MHz, (CD3)2SO-d6, δ in ppm): 1.78 (s: 3H); 2.64 (dd, J=14 and 8 Hz: 1H); 2.87 (dd, J=14 and 5.5 Hz: 1H); from 3.20 to 3.40 (mt: 2H); 3.90 (mt: 1H); 4.76 (t, J=5.5 Hz: 1H); 6.99 (dd, J=5 and 1 Hz: 1H); 7.16 (dd, J=3 and 1 Hz: 1H); 7.43 (dd, J=5 and 3 Hz: 1H); 7.70 (d, J=8.5 Hz: 1H).

Workup

  1. customis brought to a temperature of 20° C
  2. stirringstirring
  3. waitis continued for 24 hours
  4. customAfter evaporation of the reaction mixture under reduced pressure (2 kPa) at a temperature in the region of 40° C.
  5. customa solid residue is obtained
  6. extractionThis mixture is extracted with twice 100 cm3 of ethyl acetate
  7. dry with materialthe organic phase is then dried over magnesium sulfate
  8. customevaporated under reduced pressure (2 kPa) at a temperature in the region of 40° C.
  9. customto give an off-white solid which
  10. customis dried in an oven under vacuum (10 Pa) at a temperature in the region of 48° C

Sources & evidence

ORD record
ord-2d4b4194543940f2bdbdb67371d43e98
Source dataset
uspto-grants-2004_03
Patent number
US06699895B2

Reaction notes

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