Clobazam → 1-Methyl-5-phenyl-1H-1,5-benzodiazepine-2,4(3H,5H)-dione

HRID 704555Notes

Reaction equation

HRID 704555 reaction equation
[CH3:1][N:2]1[C:13](=[O:14])[CH2:12][C:10](=[O:11])[N:9]([C:15]2[CH:16]=[CH:17][CH:18]=[CH:19][CH:20]=2)[C:8]2[CH:7]=[C:6](Cl)[CH:5]=[CH:4][C:3]1=2.[OH-].[K+]>CO>[CH3:1][N:2]1[C:3]2[CH:4]=[CH:5][CH:6]=[CH:7][C:8]=2[N:9]([C:15]2[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=2)[C:10](=[O:11])[CH2:12][C:13]1=[O:14]

Participants

4

Reactant 2

HCID 2789ClobazamHCID 14797Potassium Hydroxide

Product 1

HCID 146976571-Methyl-5-phenyl-1H-1,5-benzodiazepine-2,4(3H,5H)-dioneYield 84.1%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent2×

Procedure

A suspension of 103 g of clobazam, 1 liter of methanol, 23 g of potassium hydroxide in solution in 400 ml of methanol and 50 g of Raney's nickel washed beforehand with water and with methanol, was hydrogenated for 24 hours under a pressure of 800 mbars. 1 liter of methylene chloride was added and the catalyst was filtered off. The solvents were concentrated under reduced pressure and the residue was taken up in methylene chloride. The mixture was washed with water, dried over magnesium sulfate and concentrated under reduced pressure. The product obtained was crystallized from methanol, washed with ether and dried to obtain 76.69 g of the sought product melting at 173° C.

Workup

  1. wash50 g of Raney's nickel washed beforehand with water and with methanol
  2. addition1 liter of methylene chloride was added
  3. filtrationthe catalyst was filtered off
  4. concentrationThe solvents were concentrated under reduced pressure
  5. washThe mixture was washed with water
  6. dry with materialdried over magnesium sulfate
  7. concentrationconcentrated under reduced pressure
  8. customThe product obtained
  9. customwas crystallized from methanol
  10. washwashed with ether
  11. customdried

Sources & evidence

ORD record
ord-79c2a93c1fcf4fbfb5ed262181f47bfa
Source dataset
uspto-grants-1991_01
Patent number
US04988692

Reaction notes

Loading…