Triphenylphosphine → 4-(N-t-Butoxycarbonyl-4-piperidinyloxy)-2-hydroxybenzoic acid methyl ester

HRID 128580

Reaction equation

HRID 128580 reaction equation
[OH:1][C:2]1[CH:11]=[C:10]([OH:12])[CH:9]=[CH:8][C:3]=1[C:4]([O:6][CH3:7])=[O:5].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.[C:32]([N:39]1[CH2:44][CH2:43][CH:42](O)[CH2:41][CH2:40]1)([O:34][C:35]([CH3:38])([CH3:37])[CH3:36])=[O:33].N(C(OCC)=O)=NC(OCC)=O>C1COCC1.C(OCC)(=O)C>[OH:1][C:2]1[CH:11]=[C:10]([O:12][CH:42]2[CH2:43][CH2:44][N:39]([C:32]([O:34][C:35]([CH3:38])([CH3:37])[CH3:36])=[O:33])[CH2:40][CH2:41]2)[CH:9]=[CH:8][C:3]=1[C:4]([O:6][CH3:7])=[O:5]

Participants

7

Reactant 4

HCID 11776TriphenylphosphineHCID 16523Methyl 2,4-DihydroxybenzoateHCID 220568ethyl N-ethoxycarbonyliminocarbamateHCID 643502Tert-butyl 4-hydroxypiperidine-1-carboxylate

Product 1

HCID 105940774-(N-t-Butoxycarbonyl-4-piperidinyloxy)-2-hydroxybenzoic acid methyl ester

Reagents, catalysts & solvents 2

HCID 8028TetrahydrofuranSolvent2×HCID 8857Ethyl AcetateSolvent

Procedure

Methyl 2,4-dihydroxybenzoate (5.1 g, 30.33 mmol) and triphenylphosphine (9.52 g, 36.3 mmol) were stirred in THF (200 ml) under nitrogen. The mixture was cooled in an ice bath and treated with a solution of 1-Boc-4-hydroxypiperidine (6.8 g, 33.8 mmol) and diethyl azodicarboxylate (5.73 ml, 6.34 g, 36.4 mmol) in THF (100 ml) added dropwise over 30 min. The mixture was stirred at ambient temperature for 18 hours, then diluted with ethyl acetate and washed with 1M NaOH, saturated aqueous sodium bicarbonate, and brine. The organic layer was dried over sodium sulfate, filtered, and evaporated to dryness in vacuo. The residue was chromatographed on silica gel eluted with 10% ethyl acetate in hexane, and the product fractions were evaporated to dryness in vacuo to give methyl 2-hydroxy-4-(1-Boc-4-piperidyloxy)benzoate.

Workup

  1. temperatureThe mixture was cooled in an ice bath
  2. additionadded dropwise over 30 min
  3. washwashed with 1M NaOH, saturated aqueous sodium bicarbonate, and brine
  4. dry with materialThe organic layer was dried over sodium sulfate
  5. filtrationfiltered
  6. customevaporated to dryness in vacuo
  7. customThe residue was chromatographed on silica gel
  8. washeluted with 10% ethyl acetate in hexane
  9. customthe product fractions were evaporated to dryness in vacuo

Sources & evidence

ORD record
ord-af4ac323a6bb404982f614c0b175dfe1
Source dataset
uspto-grants-1995_11
Patent number
US05464788

Linked notes

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