Hydrochloric Acid → Diethyl 4-amino-2-chloro-3-methoxybenzylphosphonate

HRID 2279864Notes

Reaction equation

HRID 2279864 reaction equation
[Cl:1][C:2]1[C:16]([O:17][CH3:18])=[C:15]([N+:19]([O-])=O)[CH:14]=[CH:13][C:3]=1[CH2:4][P:5](=[O:12])([O:9][CH2:10][CH3:11])[O:6][CH2:7][CH3:8].Cl.C([O-])([O-])=O.[Na+].[Na+]>C(O)C.C(OCC)(=O)C.[Fe]>[NH2:19][C:15]1[CH:14]=[CH:13][C:3]([CH2:4][P:5](=[O:12])([O:9][CH2:10][CH3:11])[O:6][CH2:7][CH3:8])=[C:2]([Cl:1])[C:16]=1[O:17][CH3:18]

Participants

7

Reactant 3

HCID 313Hydrochloric AcidHCID 10340Sodium CarbonateHCID 86697802Diethyl 2-chloro-3-methoxy-4-nitrobenzylphosphonate2×

Product 1

HCID 86697801Diethyl 4-amino-2-chloro-3-methoxybenzylphosphonateYield 98.8%

Reagents, catalysts & solvents 3

HCID 23925IronCatalystHCID 702EthanolSolventHCID 8857Ethyl AcetateSolvent

Procedure

To a solution of diethyl 2-chloro-3-methoxy-4-nitrobenzylphosphonate (Compound 54F, 1 g, 2.96 mmol) in ethanol (15 mL), and iron powder (1.63 g, 29.6 mmol) was added aqueous 2N HCl (5 mL). The reaction mixture was heated to reflux for 1.5 h. The reaction mixture was cooled to RT and saturated solution of Na2CO3 was added until the pH was 9. The reaction mixture was filtered through celite and concentrated to give the residue. It was dissolved in ethyl acetate (25 mL) and washed with water, dried over sodium sulfate, filtered and concentrated to give the required product (89%, 900 mg). 1H NMR (300 MHz, CDCl3) δ 7.01 (d, 1H), 6.62 (d, 1H), 4.00-4.19 (m, 4H), 3.83 (s, 3H), 3.25 (d, 2H), 1.23 (t, 6H).

Workup

  1. temperatureThe reaction mixture was heated
  2. temperatureto reflux for 1.5 h
  3. filtrationThe reaction mixture was filtered through celite and
  4. concentrationconcentrated
  5. customto give the residue
  6. washwashed with water
  7. dry with materialdried over sodium sulfate
  8. filtrationfiltered
  9. concentrationconcentrated

Sources & evidence

ORD record
ord-935a9a75c6f448cea9293dd824b60ca8
Source dataset
uspto-grants-2015_09
Patent number
US09133224B2

Reaction notes

Loading…