Allyl bromide → 2-allyl-8-methoxy-2,3,4,5-tetrahydro-1H-2-benzazepin-1-one

HRID 1655693Notes

Reaction equation

HRID 1655693 reaction equation
[CH3:1][O:2][C:3]1[CH:14]=[CH:13][C:6]2[CH2:7][CH2:8][CH2:9][NH:10][C:11](=[O:12])[C:5]=2[CH:4]=1.[H-].[Na+].[CH2:17](Br)[CH:18]=[CH2:19]>CN(C)C=O.[Cl-].[Na+].O>[CH2:19]([N:10]1[CH2:9][CH2:8][CH2:7][C:6]2[CH:13]=[CH:14][C:3]([O:2][CH3:1])=[CH:4][C:5]=2[C:11]1=[O:12])[CH:18]=[CH2:17]

Participants

6

Reactant 3

HCID 7841Allyl bromideHCID 24758Sodium hydrideHCID 112755298-Methoxy-2,3,4,5-tetrahydro-benzo[c]azepin-1-one

Product 1

HCID 229049982-allyl-8-methoxy-2,3,4,5-tetrahydro-1H-2-benzazepin-1-oneYield 83%

Reagents, catalysts & solvents 2

HCID 6228DimethylformamideSolventHCID 57417360Sodium chloride; waterSolvent

Procedure

A solution of 8-methoxy-2,3,4,5-tetrahydro-1H-2-benzazepin-1-one (10.0 g 0.052 mol) in N,N-dimethylformamide (30 mL) and allylbromide (23 mL, 0.260 mL) was treated with NaH (60% by wt. dispersion in oil, 2.50 g, 0.063 mol) and the resulting grey suspension stirred at room temperature under an atmosphere of argon. Gas evolution was noted. After 15 minutes, the solution was diluted with brine and partitioned between ethyl acetate and brine. The combined organic layers were concentrated in vacuo and purified by chromatography over silica gel eluting with a gradient of hexane to 1:1 ethyl acetate/hexane to yield 8 g (83%) of 2-allyl-8-methoxy-2,3,4,5-tetrahydro-1H-2-benzazepin-1-one as a colorless oil: 1H NMR(CDCl3) d7.23(m, 1H), 7.03(d, J=9 Hz, 1H), 6.90(dd, J=3, 9 Hz, 1H), 5.91(m, 1H), 5.23(m, 2H), 4.20(d, J=6 Hz, 2H), 3.82(s, 3H), 3.18(t, J=6 Hz, 2H), 2.72(t, J=6 Hz, 2H), 1.96(pentet, J=6 Hz, 2H); 13C NMR(CDCl3) d170.59(CO), 158.42(NCO), 136.88, 133.81, 129.43, 129.35, 129.33, 117.56, 117.54, 112.98, 55.26, 49.43, 45.37, 29.57, 29.22; MS(FAB) m/z=232.1(MH+).

Workup

  1. custompartitioned between ethyl acetate and brine
  2. concentrationThe combined organic layers were concentrated in vacuo
  3. custompurified by chromatography over silica gel eluting with a gradient of hexane to 1:1 ethyl acetate/hexane

Sources & evidence

ORD record
ord-74b50c1945774b5fb528980a00c63e26
Source dataset
uspto-grants-1993_10
Patent number
US05250679

Reaction notes

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