Reaction #4106

Reaction equation

N-benzylpiperazine

9-bromo-1,2-dihydrobenzo[b]pyrrolo[3,2,1-jk][1,4]benzodiazepine-6-one

sodium hydroxide

→

9-Bromo-6-(4-phenylmethyl-1-piperazinyl)-1,2-dihydrobenzo[b]pyrrolo[3,2,1-jk][1,4]benzodiazepine

Solvents

toluene

Conditions

Workup

1. 1
   Temperaturewas heated under nitrogen until a solution
2. 2
   Otherresulted
3. 3
   TemperatureThe mixture was heated
4. 4
   Temperatureunder reflux for 3 hours
5. 5
   Otherthe layers were separated
6. 6
   ExtractionThe aqueous phase was extracted further with 300 ml of toluene
7. 7
   Washwashed once with 2N sodium hydroxide solution, twice with water
8. 8
   Dryingdried over anhydrous sodium sulfate
9. 9
   Concentrationconcentrated in vacuo
10. 10
    Othercrystallized
11. 11
    OtherRecrystallization from a solution of dichloromethane (10 ml) to which methanol (50 ml)
12. 12
    workup.ADDITIONwas added
13. 13
    Otherafforded the analytical sample, mp 129°-131° C.

Procedure

A stirred mixture of 7.88 g (0.0250 mole) of 9-bromo-1,2-dihydrobenzo[b]pyrrolo[3,2,1-jk][1,4]benzodiazepine-6-one and 1200 ml of toluene was heated under nitrogen until a solution resulted. Then there was added 44.1 g (0.250 mole) of N-benzylpiperazine, followed by 14.2 g (0.0750 mole) of titanium tetrachloride. The mixture was heated under reflux for 3 hours, cooled to room temperature and treated with 500 ml of 2N sodium hydroxide. After stirring vigorously for 15 minutes, the layers were separated. The aqueous phase was extracted further with 300 ml of toluene. The toluene layers were combined, washed once with 2N sodium hydroxide solution, twice with water, dried over anhydrous sodium sulfate, and concentrated in vacuo. The residue was taken up in 50 ml of hot methanol, from which 7.00 g (59%) of product crystallized. Recrystallization from a solution of dichloromethane (10 ml) to which methanol (50 ml) was added afforded the analytical sample, mp 129°-131° C.

Source