Pyridine → 4-Nitrophenyl methoxycarbamate

HRID 589171Notes

Reaction equation

HRID 589171 reaction equation
Cl.[O:2]([NH2:4])[CH3:3].N1C=CC=CC=1.[C:11](Cl)(=[O:22])[O:12][C:13]1[CH:18]=[CH:17][C:16]([N+:19]([O-:21])=[O:20])=[CH:15][CH:14]=1>ClCCl>[CH3:3][O:2][NH:4][C:11](=[O:22])[O:12][C:13]1[CH:14]=[CH:15][C:16]([N+:19]([O-:21])=[O:20])=[CH:17][CH:18]=1

Participants

5

Reactant 3

HCID 1049PyridineHCID 821294-Nitrophenyl chloroformateHCID 521874O-Methylhydroxylamine hydrochloride

Product 1

HCID 115647354-Nitrophenyl methoxycarbamateYield 36.1%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent3×

Procedure

Methoxylamine hydrochloride (1.00 g, 12.0 mmol) was suspended in a mixture of dry pyridine (0.97 mL, 12.0 mmol) and dichloromethane (24 mL), and a solution of 4-nitrophenyl chlorocarbonate (2.41 g, 12.0 mmol) in dichloromethane (12 mL) was added over 30 min with stirring. The resulting heavy white suspension was warmed to reflux, refluxed for 6 h, and cooled to room temperature. The suspension was diluted with dichloromethane and washed with 1M HCl, keeping the emulsion with the aqueous layer, and the aqueous layer was re-extracted with dichloromethane. The combined organic phase was washed with water, saturated aqueous sodium bicarbonate and brine, keeping any emulsions with the aqueous layer, and then dried over magnesium sulfate and concentrated under reduced pressure. The crude product was purified by chromatography (90 g silica gel, 20-40% EtOAc/hexanes) to give the title compound (0.92 g) as a white crystalline solid. A second set of less pure product fractions was isolated to give additional product (0.21 g) as a white solid.

Workup

  1. temperatureThe resulting heavy white suspension was warmed
  2. temperatureto reflux
  3. temperaturerefluxed for 6 h
  4. washwashed with 1M HCl
  5. extractionthe aqueous layer was re-extracted with dichloromethane
  6. washThe combined organic phase was washed with water, saturated aqueous sodium bicarbonate and brine
  7. dry with materialdried over magnesium sulfate
  8. concentrationconcentrated under reduced pressure
  9. customThe crude product was purified by chromatography (90 g silica gel, 20-40% EtOAc/hexanes)

Sources & evidence

ORD record
ord-0a436412722542849bb7c01906f28714
Source dataset
uspto-grants-2016_01
Patent number
US09227971B2

Reaction notes

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