N-bromobutanimide → 7-Bromo-3,4-dihydro-4-methyl-2H-1,4-benzoxazine

HRID 970319Notes

Reaction equation

HRID 970319 reaction equation
[CH3:1][N:2]1[C:7]2[CH:8]=[CH:9][CH:10]=[CH:11][C:6]=2[O:5][CH2:4][CH2:3]1.[Br:12]N1C(=O)CCC1=O>CN(C=O)C.C(Cl)Cl>[Br:12][C:10]1[CH:9]=[CH:8][C:7]2[N:2]([CH3:1])[CH2:3][CH2:4][O:5][C:6]=2[CH:11]=1

Participants

5

Reactant 2

HCID 67184N-bromobutanimideHCID 37550242H-1,4-Benzoxazine, 3,4-dihydro-4-methyl-

Product 1

HCID 27764057-Bromo-3,4-dihydro-4-methyl-2H-1,4-benzoxazineYield 78%

Reagents, catalysts & solvents 2

HCID 6228DimethylformamideSolventHCID 6344DichloromethaneSolvent

Conditions

Temperature
80 °C

Procedure

A mixture of the 104B (0.225 g, 1.51 mmol) and N-bromosuccinimide (0.269 g, 1.51 mmol) in DMF (10 mL) was heated at 80° C. overnight. The reaction mixture was dissolved in DCM and washed with water several times. The organic layer was collected, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel chromatography to give 0.267 g (78%) of 104C. HPLC retention time=3.32 min. (Condition B) and LC/MS M+1=230.03 (d). 1H-NMR (500 MHz, CDCl3) δ 2.83 (s, 3H), 3.22 (t, 2H), 4.26 (t, 2H), 6.49 (d, 1H, J=8.8 Hz), 6.87 (s, 1H), and 6.90 (d, 1H, J=8.8 Hz).

Workup

  1. washwashed with water several times
  2. customThe organic layer was collected
  3. dry with materialdried over anhydrous sodium sulfate
  4. concentrationconcentrated under reduced pressure
  5. customThe residue was purified by silica gel chromatography

Sources & evidence

ORD record
ord-1d849650a5174a5a9eb39cb8520d265b
Source dataset
uspto-grants-2007_12
Patent number
US07312209B2

Reaction notes

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