Dimethylformamide → 6-Bromo-2,2,7-trimethyl-4H-benzo[1,4]oxazin-3-one

HRID 2239239Notes

Reaction equation

HRID 2239239 reaction equation
[CH3:1][C:2]1([CH3:14])[C:7](=[O:8])[NH:6][C:5]2[CH:9]=[CH:10][C:11]([CH3:13])=[CH:12][C:4]=2[O:3]1.CN(C=O)C.C1C(=O)N([Br:27])C(=O)C1>C(Cl)(Cl)Cl>[Br:27][C:10]1[C:11]([CH3:13])=[CH:12][C:4]2[O:3][C:2]([CH3:14])([CH3:1])[C:7](=[O:8])[NH:6][C:5]=2[CH:9]=1

Participants

5

Reactant 3

HCID 6228DimethylformamideHCID 67184N-bromobutanimideHCID 594182682,2,7-Trimethyl-2H-benzo[b][1,4]oxazin-3(4H)-one

Product 1

HCID 685856146-Bromo-2,2,7-trimethyl-4H-benzo[1,4]oxazin-3-oneYield 58%

Reagents, catalysts & solvents 1

HCID 6212ChloroformSolvent

Procedure

A solution of Compound 1A (4.24 g, 22.2 mmol) in 150 mL of chloroform was treated with 5 mL of dry DMF followed by 4.4 g (24.4 mmol) of NBS at room temperature. After 4 hours, the reaction was quenched with 150 mL of a saturated sodium thiosulfate solution. The aqueous layer was extracted with chloroform and the combined organic layers were dried with magnesium sulfate, filtered, and excess solvent removed on the rotary evaporator. The crude product was purified via silica gel chromatography (5% EtOAc/Hexanes) to yield 3.48 g of brominated product (58%). MS (electrospray): mass calculated for C11H12BrNO2, 269.01; m/z found 268, [M+H]+.

Workup

  1. customthe reaction was quenched with 150 mL of a saturated sodium thiosulfate solution
  2. extractionThe aqueous layer was extracted with chloroform
  3. dry with materialthe combined organic layers were dried with magnesium sulfate
  4. filtrationfiltered
  5. customexcess solvent removed on the rotary evaporator
  6. customThe crude product was purified via silica gel chromatography (5% EtOAc/Hexanes)

Sources & evidence

ORD record
ord-164356835d1e424c8a5794ac98b8a960
Source dataset
uspto-grants-2010_05
Patent number
US07723326B2

Reaction notes

Loading…