7-Bromo-5-(2-fluorophenyl)-1,3-dihydro-2H-1,4-benzodiazepin-2-one → 7-bromo-5-(2-fluorophenyl)-2,3-dihydro-1H-1,4-benzodiazepine

HRID 1365057Notes

Reaction equation

HRID 1365057 reaction equation
[Br:1][C:2]1[CH:3]=[CH:4][C:5]2[NH:11][C:10](=O)[CH2:9][N:8]=[C:7]([C:13]3[CH:18]=[CH:17][CH:16]=[CH:15][C:14]=3[F:19])[C:6]=2[CH:20]=1.[H-].[Al+3].[Li+].[H-].[H-].[H-]>O1CCCC1>[Br:1][C:2]1[CH:3]=[CH:4][C:5]2[NH:11][CH2:10][CH2:9][N:8]=[C:7]([C:13]3[CH:18]=[CH:17][CH:16]=[CH:15][C:14]=3[F:19])[C:6]=2[CH:20]=1

Participants

4

Reactant 2

HCID 129470247-Bromo-5-(2-fluorophenyl)-1,3-dihydro-2H-1,4-benzodiazepin-2-oneHCID 21226445Aluminium lithium hydride

Product 1

HCID 577324247-bromo-5-(2-fluorophenyl)-2,3-dihydro-1H-1,4-benzodiazepineYield 52.2%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

A round-bottomed flask was charged with 7-bromo-5-(2-fluorophenyl)-1,3-dihydro-2H-1,4-benzodiazepin-2-one (500 mg) and tetrahydrofuran (20 mL). To this mixture was added lithium aluminum hydride (1.8 mL of 1M solution in tetrahydrofuran). The reaction was stirred overnight at room temperature, then quenched with water and 10% sodium hydroxide. The quenched mixture was filtered through Celite and the filter was washed with ethyl acetate. The filtrate was dried over magnesium sulfate, filtered and concentrated to an oil. Silica gel purification provided 7-bromo-5-(2-fluorophenyl)-2,3-dihydro-1H-1,4-benzodiazepine (250 mg) as a yellow powder. H1 NMR (d6-dmso): 7.43-7.50 (m, 1H), 7.40 (dt, 1H), 7.18-7.28 (m, 3H), 6.75-6.81 (m, 2H), 6.71 (d, 1H), 3.95 (m, 2H), 3.49 (m, 2H). Mass (ES+)=319.1 (100%).

Workup

  1. customquenched with water and 10% sodium hydroxide
  2. filtrationThe quenched mixture was filtered through Celite
  3. washthe filter was washed with ethyl acetate
  4. dry with materialThe filtrate was dried over magnesium sulfate
  5. filtrationfiltered
  6. concentrationconcentrated to an oil
  7. customSilica gel purification

Sources & evidence

ORD record
ord-1de3bd6af1a74c39a5c20a8966452836
Source dataset
uspto-grants-2011_02
Patent number
US07888503B2

Reaction notes

Loading…