Water → 3-phenyl-3,4-dihydro-2H-1,4-benzoxazine

HRID 2415797Notes

Reaction equation

HRID 2415797 reaction equation
[C:1]1([C:7]2[CH2:8][O:9][C:10]3[CH:16]=[CH:15][CH:14]=[CH:13][C:11]=3[N:12]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[BH4-].[Na+].O>C(O)C>[C:1]1([CH:7]2[NH:12][C:11]3[CH:13]=[CH:14][CH:15]=[CH:16][C:10]=3[O:9][CH2:8]2)[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=1

Participants

5

Reactant 3

HCID 962WaterHCID 14817833-phenyl-2H-1,4-benzoxazineHCID 4311764Sodium borohydride

Product 1

HCID 124745723-phenyl-3,4-dihydro-2H-1,4-benzoxazineYield 93%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Conditions

Temperature
90 °C

Procedure

To a slurry of 3-phenyl-2H-1,4-benzoxazine (17 g, 81.2 mmol) in 100 mL absolute ethanol is added sodium borohydride (6.07 g, 162.4 mmol) and water (25 mL). The mixture is heated at 90° C. for 2 h. The mixture is cooled and concentrated, then partitioned between CH2Cl2 and water. The organic layer is washed twice with water (200 mL), dried over magnesium sulfate and concentrated. The resulting oil is dried under high vacuum to give 15.95 g (93%) of 3-phenyl-3,4-dihydro-2H-1,4-benzoxazine.

Workup

  1. temperatureThe mixture is cooled
  2. concentrationconcentrated
  3. custompartitioned between CH2Cl2 and water
  4. washThe organic layer is washed twice with water (200 mL)
  5. dry with materialdried over magnesium sulfate
  6. concentrationconcentrated
  7. customThe resulting oil is dried under high vacuum

Sources & evidence

ORD record
ord-7efe34ea7728456ca82a8b67aa03f6d0
Source dataset
uspto-grants-2004_11
Patent number
US06821970B2

Reaction notes

Loading…