Reaction #168607

ord-05728a609c1b45cb84a7e834cb10bf15

Conditions

Temperature
-45°CELSIUS
Detailed conditions
See reaction.notes.procedure_details.

Workup

  1. 1
    workup.STIRRINGwith stirring
  2. 2
    workup.STIRRINGThe reaction mixture was stirred at this temperature for 3 h
  3. 3
    workup.WAITto warn to room temperature over 16 h
  4. 4
    Washwashed with water (250 mL)
  5. 5
    ExtractionThe aqueous phase was extracted with DCM (3×50 mL)
  6. 6
    Washthe combined organic phase washed with brine (50 mL)
  7. 7
    Dryingdried (MgSO4)
  8. 8
    Otherevaporated in vacuo
  9. 9
    workup.DISSOLUTIONThe residue was dissolved in ether (30 mL)
  10. 10
    Otherthe solid precipitate removed by filtration
  11. 11
    Otherthe filtrate was evaporated in vacuo
  12. 12
    workup.DISSOLUTIONThe residue was dissolved in hexane (50 mL)
  13. 13
    Otherthe solid precipitate removed by filtration
  14. 14
    Otherthe filtrate was evaporated in vacuo

Procedure

To a stirred solution of DMSO (2.4 mL, 2.8 eq, 33.82 mmol) in DCM (30 mL) under an argon atmosphere at −45° C., was added oxalyl chloride (2 M in DCM, 8.45 mL, 1.40 eq, 16.9 mmol), dropwise. The reaction mixture was stirred at −45° C. for 1 h, after which time a solution of (S)-2-(trityl-amino)-butan-1-ol (4 g, 1 eq, 12.07 mmol) in DCM (30 mL) was added dropwise with stirring. The reaction mixture was stirred at this temperature for 3 h, when TLC (hexane:ether; 80:20) indicated that the reaction had gone to completion. To the reaction mixture was added a solution of TEA (8.4 mL, 5 eq, 60.27 mmol) in DCM (30 mL), and the solution allowed to warn to room temperature over 16 h. The reaction mixture was diluted with more DCM (100 mL) and washed with water (250 mL). The aqueous phase was extracted with DCM (3×50 mL), and the combined organic phase washed with brine (50 mL), dried (MgSO4) and evaporated in vacuo. The residue was dissolved in ether (30 mL), the solid precipitate removed by filtration and the filtrate was evaporated in vacuo. The residue was dissolved in hexane (50 mL), the solid precipitate removed by filtration and the filtrate was evaporated in vacuo to afford the title compound as a light yellow oil. Yield: 3.64 g (91%). 1H-NMR (d6-DMSO, 250 MHz): δ 0.77 (t, 3H, J=7.42 Hz, —NHCH(CH2CH3)CHO), 1.37-1.59 (m, 2H, —NHCH(CH2CH3)CHO), 2.93 (m, 1H, —NHCH(CH2CH3)CHO), 3.62 (d, 1H, J=5.84 Hz, —NHCH(CH2CH3)CHO), 7.16-7.46 (m, 15H, 3×Ph), 8.77 (d, 1H, J=3.00 Hz, —NHCH(CH2CH3)CHO).

Source

DOI: 10.6084/m9.figshare.5104873.v1Patent: US08846696B2uspto-grants-2014_09