4-Nitrophenol → 4-nitrophenyl 6-fluoro-3,4-dihydro-2H-chromen-2-carboxylate

HRID 2423261Notes

Reaction equation

HRID 2423261 reaction equation
[F:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[O:8][CH:7]([C:12]([OH:14])=[O:13])[CH2:6][CH2:5]2.C(Cl)(=O)C(Cl)=O.ClCCl.[N+:24]([C:27]1[CH:32]=[CH:31][C:30](O)=[CH:29][CH:28]=1)([O-:26])=[O:25]>N1C=CC=CC=1>[F:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[O:8][CH:7]([C:12]([O:14][C:30]1[CH:31]=[CH:32][C:27]([N+:24]([O-:26])=[O:25])=[CH:28][CH:29]=1)=[O:13])[CH2:6][CH2:5]2

Participants

6

Reactant 4

HCID 9804-NitrophenolHCID 6344DichloromethaneHCID 65578Oxalyl chlorideHCID 153828436-Fluoro-3,4-dihydro-2H-1-benzopyran-2-carboxylic acid

Product 1

HCID 672453244-nitrophenyl 6-fluoro-3,4-dihydro-2H-chromen-2-carboxylateYield 40.5%

Reagents, catalysts & solvents 1

HCID 1049PyridineSolvent

Procedure

A 50 ml rbf was charged with 6-fluoro-3,4-dihydro-2H-chromen-2-carboxylic acid (10.0 g, 51.0 mmol), oxalyl chloride (9.71 g, 76.5 mmol) and dichloromethane (24.9 g) under nitrogen atmosphere at room temperature. The mixture was stirred for 17 h at room temperature and then concentrated in vacuo at 30° C. The residue was dissolved in toluene (75 ml) and stirred at rt. 4-nitrophenol (7.05 g, 51.02 mmol) was added to the reaction mixture, followed by pyridine (5 ml) over the period of 5 min. The slurry was heated to 80° C., stirred for 3 h at this temperature and then cooled to 25° C. The solid was separated by filtration and the filtered solution washed with 2M aqueous sodium hydroxide (65 g), with a saturated solution of sodium bicarbonate (2×51 g), and with demi water (53 g). The separated organic phase was concentrated in vacuo and dried via azeotropic distillation to furnish 4-nitrophenyl 6-fluoro-3,4-dihydro-2H-chromen-2-carboxylate as a vetrous oil (7.71 g, 40.5% yield, 85.0 A %).

Workup

  1. concentrationconcentrated in vacuo at 30° C
  2. dissolutionThe residue was dissolved in toluene (75 ml)
  3. stirringstirred at rt
  4. temperatureThe slurry was heated to 80° C.
  5. stirringstirred for 3 h at this temperature
  6. temperaturecooled to 25° C
  7. customThe solid was separated by filtration
  8. washthe filtered solution washed with 2M aqueous sodium hydroxide (65 g), with a saturated solution of sodium bicarbonate (2×51 g)
  9. concentrationThe separated organic phase was concentrated in vacuo
  10. customdried via azeotropic distillation

Sources & evidence

ORD record
ord-43062a4410174ce6bb26380801ed3c0b
Source dataset
uspto-grants-2011_06
Patent number
US07960572B2

Reaction notes

Loading…