Hydrochloric Acid → Fmoc-D-allo-Thr-OH

HRID 1738771Notes

Reaction equation

HRID 1738771 reaction equation
[NH2:1][C@@H:2]([C:6]([OH:8])=[O:7])[C@@H:3]([CH3:5])[OH:4].C([O-])(O)=O.[Na+].[C:14](ON1C(=O)CCC1=O)([O:16][CH2:17][CH:18]1[C:30]2[C:25](=[CH:26][CH:27]=[CH:28][CH:29]=2)[C:24]2[C:19]1=[CH:20][CH:21]=[CH:22][CH:23]=2)=[O:15].Cl>O.O1CCOCC1>[NH:1]([C:14]([O:16][CH2:17][CH:18]1[C:19]2[C:24](=[CH:23][CH:22]=[CH:21][CH:20]=2)[C:25]2[C:30]1=[CH:29][CH:28]=[CH:27][CH:26]=2)=[O:15])[C@@H:2]([C:6]([OH:8])=[O:7])[C@@H:3]([CH3:5])[OH:4]

Participants

7

Reactant 4

HCID 313Hydrochloric AcidHCID 90624D-AllothreonineHCID 134122N-(9-Fluorenylmethoxycarbonyloxy)succinimideHCID 516892Sodium Bicarbonate

Product 1

HCID 6992534Fmoc-D-allo-Thr-OHYield 80%

Reagents, catalysts & solvents 2

HCID 962WaterSolvent2×HCID 312751,4-DioxaneSolvent

Procedure

All Fmoc amino acids were synthesized from the corresponding free amino acids by the following general procedure. To a solution of D-allo-Thr (25) (1.62 g, 13.6 mmol) and NaHCO3 (3.4 g, 41 mmol) in H2O (60 mL) was added a solution of Fmoc-OSu (4.58 g, 13.6 mmol) in dioxane (60 mL) and the turbid reaction mixture stirred at RT overnight. The mixture was then diluted with H2O, acidified to pH≤4 by addition of 37% HCl and extracted with ethyl acetate (3×100 mL). The combined ethyl acetate extracts were washed with saturated NaCl (2×100 mL), dried (MgSO4) and taken to dryness by rotary evaporation to give a colorless oil which was crystallized from ethyl acetate/hexane, yielding Fmoc-D-allo-Thr (26) as white crystals (3.7 g, 80%), mp 152°-153° C. Anal. (C19H19NO5) C, H, N.

Workup

  1. customthe turbid reaction mixture
  2. extractionextracted with ethyl acetate (3×100 mL)
  3. washThe combined ethyl acetate extracts were washed with saturated NaCl (2×100 mL)
  4. dry with materialdried (MgSO4)
  5. customtaken to dryness by rotary evaporation
  6. customto give a colorless oil which
  7. customwas crystallized from ethyl acetate/hexane

Sources & evidence

ORD record
ord-2b507a393fe045ceb3e91a71c5f6ca36
Source dataset
uspto-grants-1999_10
Patent number
US05965524

Reaction notes

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