Chlorine → (S)-7-amino-6-chloro-5-(o-fluorophenyl)-1,3-dihydro-1,3-dimethyl-2H-1,4-benzodiazepin-2-one

HRID 848529Notes

Reaction equation

HRID 848529 reaction equation
[NH2:1][C:2]1[CH:3]=[CH:4][C:5]2[N:11]([CH3:12])[C:10](=[O:13])[C@H:9]([CH3:14])[N:8]=[C:7]([C:15]3[CH:20]=[CH:19][CH:18]=[CH:17][C:16]=3[F:21])[C:6]=2[CH:22]=1.[Cl:23]Cl>>[NH2:1][C:2]1[CH:3]=[CH:4][C:5]2[N:11]([CH3:12])[C:10](=[O:13])[C@H:9]([CH3:14])[N:8]=[C:7]([C:15]3[CH:20]=[CH:19][CH:18]=[CH:17][C:16]=3[F:21])[C:6]=2[C:22]=1[Cl:23]

Participants

3

Procedure

4 g (0.011 M) of (S)-7-amino-5-(o-fluorophenyl)-1,3-dihydro-1,3-dimethyl-2H-1,4-benzodiazepin-2-one are dissolved in 35 ml of ice-cold concentrated hydrochloric acid at -10° C. and chlorine gas is conducted in at -10° C. for 1 hour. The mixture is concentrated at 0°-5° C. using a high vacuum cooling trap and a soda lime tower under a high vacuum (1-2 mmHg). The residue is made alkaline with a mixture of ice and 10% sodium bicarbonate solution. The mixture is extracted with methylene chloride and the extract is dried over sodium sulphate, filtered and concentrated. The remaining oil is purified on a 300 g silica gel column using methylene chloride and then methylene chloride/ethyl acetate (20:1) as the eluting agent. This operation is repeated once on a 120 g silica gel column using methylene chloride and then methylene chloride/ethyl acetate (20:1) as the eluting agent. After crystallisation from ethyl acetate/ether, there is obtained (S)-7-amino-6-chloro-5-(o-fluorophenyl)-1,3-dihydro-1,3-dimethyl-2H-1,4-benzodiazepin-2-one which melts at 222°-226° C.; [α]25D =+92° (in methylene chloride; 0.5%).

Workup

  1. concentrationThe mixture is concentrated at 0°-5° C.
  2. temperaturecooling trap
  3. additionwith a mixture of ice and 10% sodium bicarbonate solution
  4. extractionThe mixture is extracted with methylene chloride
  5. dry with materialthe extract is dried over sodium sulphate
  6. filtrationfiltered
  7. concentrationconcentrated
  8. customThe remaining oil is purified on a 300 g silica gel column
  9. customAfter crystallisation from ethyl acetate/ether

Sources & evidence

ORD record
ord-6e1ed3e4bf7b439a9bd6c96e01f33f93
Source dataset
uspto-grants-1981_10
Patent number
US04296031

Reaction notes

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