N-[5-methyl-2-(2,3-dihydro-1H-indol-1-yl)phenyl]-4-methyl-1-piperazinecarboxamide → 6-(4-Methyl-1-piperazinyl)-9-methyl-1,2-dihydrobenzo[b]pyrrolo[3,2,1-jk][1,4]benzodiazepine
Reaction equation
[CH3:1][C:2]1[CH:3]=[CH:4][C:5]([N:18]2[C:26]3[C:21](=[CH:22][CH:23]=[CH:24][CH:25]=3)[CH2:20][CH2:19]2)=[C:6]([NH:8][C:9]([N:11]2[CH2:16][CH2:15][N:14]([CH3:17])[CH2:13][CH2:12]2)=O)[CH:7]=1>P(Cl)(Cl)(Cl)=O>[CH3:1][C:2]1[CH:3]=[CH:4][C:5]2[N:18]3[CH2:19][CH2:20][C:21]4[C:26]3=[C:25]([CH:24]=[CH:23][CH:22]=4)[C:9]([N:11]3[CH2:16][CH2:15][N:14]([CH3:17])[CH2:13][CH2:12]3)=[N:8][C:6]=2[CH:7]=1Participants
3
Procedure
A stirred mixture of 35.1 (0.10 mole) of N-[5-methyl-2-(2,3-dihydro-1H-indol-1-yl)phenyl]-4-methyl-1-piperazinecarboxamide of Example 5c in 500 ml of phosphorus oxychloride was refluxed for 6 hours under nitrogen, then cooled to room temperature. The excess phosphorus oxychloride was removed at aspirator pressure with gentle warming. The residue was chilled in an ice-bath (with exclusion of moisture), and then treated first with 250 ml of ice-cold 2N-NaOH, then with 500 ml of chloroform. The mixture was stirred vigorously until all the material passed into solution. The organic phase was separated, washed thrice with water, and concentrated in vacuo to an oil. This was dissolved in 100 ml of boiling acetone, then allowed to crystallize at room temperature to afford 13.5 g (41% overall yield) of 9-methyl-6-(4-methyl-1-piperazinyl)-1,2-dihydrobenzo[b]pyrrolo[3,2,1-jk][1,4]-benzodiazepine, m.p. 160°-162° C.