Citric Acid → (R)-tert-butyl (2-hydroxy-1-(4-hydroxyphenyl)ethyl)carbamate

HRID 454971

Reaction equation

HRID 454971 reaction equation
C[O:2][C:3](=O)[C@H:4]([NH:12][C:13]([O:15][C:16]([CH3:19])([CH3:18])[CH3:17])=[O:14])[C:5]1[CH:10]=[CH:9][C:8]([OH:11])=[CH:7][CH:6]=1.B.[Li].C(O)(=O)CC(CC(O)=O)(C(O)=O)O>C1COCC1>[C:16]([O:15][C:13](=[O:14])[NH:12][C@H:4]([C:5]1[CH:10]=[CH:9][C:8]([OH:11])=[CH:7][CH:6]=1)[CH2:3][OH:2])([CH3:19])([CH3:17])[CH3:18]

Participants

5

Reactant 3

HCID 311Citric AcidHCID 10934864Methyl (2R)-2-{[(tert-butoxy)carbonyl]amino}-2-(4-hydroxyphenyl)acetateHCID 178419226HCID 178419226, compound

Product 1

HCID 67073553(R)-tert-butyl (2-hydroxy-1-(4-hydroxyphenyl)ethyl)carbamate

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

(R)-tert-Butoxycarbonylamino-(4-hydroxy-phenyl)-acetic acid methyl ester (10 mmol), Lithium Boron hydride (1.089 g, 50 mmol) and THF (50 ml) were combined and stirred at room temperature overnight. Ice (20 ml) was added into the reaction mixture with stirring. Saturated citric acid was then added dropwise until no more bubbles were generated. The reaction mixture was transferred to a separatory funnel. The aqueous layer was extracted with ethyl acetate (3×30 ml). The combined organic layers were washed with saturated NH4Cl and water sequentially, then dried over MgSO4, filtered and concentrated to give a white crude solid (2.92 g, crude product) with some impurity: 1H NMR (400 MHz, MeOD) δ ppm 7.14 (d, J=8.6 Hz, 2H), 6.76 (d, J=8.6 Hz, 2H), 4.56 (m, 1H), 3.63 (m, 2H), 1.43 (s, 9H); LCMS (ESI) m/e 254.1 [(M+H)+, calcd for C13H20NO4 254.3].

Workup

  1. stirringwith stirring
  2. customThe reaction mixture was transferred to a separatory funnel
  3. extractionThe aqueous layer was extracted with ethyl acetate (3×30 ml)
  4. washThe combined organic layers were washed with saturated NH4Cl and water sequentially
  5. dry with materialdried over MgSO4
  6. filtrationfiltered
  7. concentrationconcentrated
  8. customto give a white crude solid (2.92 g, crude product) with some impurity

Sources & evidence

ORD record
ord-ce7005a1ecff4913a3d6285bed6bfa2d
Source dataset
uspto-grants-2013_07
Patent number
US08497271B2

Linked notes

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