Benzyl Bromide → 4-benzyl-6-bromo-spiro[3H-1,4-benzoxazine-2,1-cyclopropane]

HRID 72592Notes

Reaction equation

HRID 72592 reaction equation
[Br:1][C:2]1[CH:3]=[CH:4][C:5]2[O:12][C:9]3([CH2:11][CH2:10]3)[CH2:8][NH:7][C:6]=2[CH:13]=1.C(=O)([O-])[O-].[K+].[K+].[CH2:20](Br)[C:21]1[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1>CN(C=O)C>[CH2:20]([N:7]1[C:6]2[CH:13]=[C:2]([Br:1])[CH:3]=[CH:4][C:5]=2[O:12][C:9]2([CH2:10][CH2:11]2)[CH2:8]1)[C:21]1[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1

Participants

5

Conditions

Temperature
60 °C

Procedure

To a stirred solution of 6-bromospiro[3,4-dihydro-1,4-benzoxazine-2,1′-cyclopropane] (3.11 g, 12.9 mmol) in DMF (20 mL) was added potassium carbonate (3.6 g, 26.0 mmol) and benzyl bromide (1.61 mL, 13.6 mmol). The reaction mixture was heated at 60° C. for 6 h then cooled to room temperature and quenched by the addition of water. The reaction mixture was extracted with ethylacetate (2×50 mL) and the combined organic layers were washed with water (20 mL) and brine (20 mL), then dried over sodium sulfate, filtered and concentrated. The crude product was purified by silica gel column chromatography to furnish 4-benzyl-6-bromo-spiro[3H-1,4-benzoxazine-2,1′-cyclopropane] (1.13 g).

Workup

  1. temperaturethen cooled to room temperature
  2. customquenched by the addition of water
  3. extractionThe reaction mixture was extracted with ethylacetate (2×50 mL)
  4. washthe combined organic layers were washed with water (20 mL) and brine (20 mL)
  5. dry with materialdried over sodium sulfate
  6. filtrationfiltered
  7. concentrationconcentrated
  8. customThe crude product was purified by silica gel column chromatography

Sources & evidence

ORD record
ord-612f7ee0699e48ccb5b343cb448e333b
Source dataset
uspto-grants-2014_09
Patent number
US08828951B2

Reaction notes

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