Toluene → diethyl pyridin-4-ylphosphonate

HRID 1013514Notes

Reaction equation

HRID 1013514 reaction equation
Cl.Br[C:3]1[CH:8]=[CH:7][N:6]=[CH:5][CH:4]=1.[P:9]([O-:16])([O:13][CH2:14][CH3:15])[O:10][CH2:11][CH3:12].C1(C)C=CC=CC=1>C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1.O>[N:6]1[CH:7]=[CH:8][C:3]([P:9](=[O:16])([O:13][CH2:14][CH3:15])[O:10][CH2:11][CH3:12])=[CH:4][CH:5]=1

Participants

6

Reactant 3

HCID 1140TolueneHCID 881004-Bromopyridinium chlorideHCID 3780918Diethylphosphite

Product 1

HCID 3623756diethyl pyridin-4-ylphosphonate

Reagents, catalysts & solvents 2

HCID 178418397HCID 178418397, compoundCatalystHCID 962WaterSolvent

Procedure

4-Bromopyridine hydrochloride (8 g, 41.1 mmol), diethyl phosphite (8.23 mL, 63.8 mmol), tetrakis(triphenylphosphine)palladium(0) (1.189 g, 1.029 mmol) and TEA (17.20 mL, 123 mmol) were stirred in refluxing toluene (160 mL) overnight. Room temperature was attained, water was added and the organic layer separated. The aqueous phase was extracted with EtOAc (×2). The combined organic extracts were washed with brine, dried over MgSO4 and concentrated in vacuo. Purification of the residue by MPLC (EtOAc) gave diethyl pyridin-4-ylphosphonate as a pale yellow oil. 1H NMR (DMSO-d6, 600 MHz) δ 8.75 (m, 2H), 7.61 (m, 2H), 4.03 (m, 4H), 1.21 (t, J=7.2 Hz, 6H). MS: cal'd 216 (MH+), exp 216 (MH+).

Workup

  1. customRoom temperature
  2. customthe organic layer separated
  3. extractionThe aqueous phase was extracted with EtOAc (×2)
  4. washThe combined organic extracts were washed with brine
  5. dry with materialdried over MgSO4
  6. concentrationconcentrated in vacuo
  7. customPurification of the residue by MPLC (EtOAc)

Sources & evidence

ORD record
ord-0d8b99b1e10f43fab9cca93f069dee2c
Source dataset
uspto-grants-2011_07
Patent number
US07981874B2

Reaction notes

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