Sodium Hydroxide → 5,6,10,11-Tetrahydro-3-methoxy-8-methyl-benzo[g]pyrazino[1,2-a]indole fumarate

HRID 486583Notes

Reaction equation

HRID 486583 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[CH:5][C:6]2[C:14]3[N:13]([CH2:15][CH2:16][NH:17][C:18](=O)[CH3:19])[CH:12]=[CH:11][C:10]=3[CH2:9][CH2:8][C:7]=2[CH:21]=1.P(Cl)(Cl)(Cl)=O.[OH-].[Na+].[C:29]([OH:36])(=[O:35])/[CH:30]=[CH:31]/[C:32]([OH:34])=[O:33]>C(O)C>[C:29]([OH:36])(=[O:35])/[CH:30]=[CH:31]/[C:32]([OH:34])=[O:33].[CH3:1][O:2][C:3]1[CH:4]=[CH:5][C:6]2[C:14]3[N:13]4[CH2:15][CH2:16][N:17]=[C:18]([CH3:19])[C:12]4=[CH:11][C:10]=3[CH2:9][CH2:8][C:7]=2[CH:21]=1

Participants

6

Reactant 4

HCID 14798Sodium HydroxideHCID 24813Phosphorus oxychlorideHCID 444972Fumaric AcidHCID 19036463HCID 19036463, compound

Product 1

HCID 190952735,6,10,11-Tetrahydro-3-methoxy-8-methyl-benzo[g]pyrazino[1,2-a]indole fumarateYield 49%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Conditions

Temperature
50 °C

Procedure

N-[2-(4,5-Dihydro-7-methoxy-1H-benzo[g]indol-1-yl)ethyl]acetamide (14.5 g) was treated with 50 ml of phosphorus oxychloride under argon and the mixture was stirred at 50° C. for 30 minutes. The cooled mixture was added to 5000 g of ice-water and treated with 500 ml of 28% sodium hydroxide solution. The mixture was extracted once with 1000 ml of methylene chloride and twice with 500 ml of methylene chloride each time, the organic phases were combined, dried with MgSO4 and freed from solvent. The residue, 14.6 g of brown oil, was chromatographed on 220 g of aluminium oxide (neutral, III) with methylene chloride as the eluent. 1.3 g of a total of 10.3 g of crude product were dissolved in a 25-fold amount of ethanol and treated with 1.1 equivalents of a saturated solution of fumaric acid in ethanol. There were obtained 1.2 g (49%) of 5,6,10,11-tetrahydro-3-methoxy-8-methyl-benzo[g]pyrazino[1,2-a]indole fumarate (1:1); m.pt.: 202°-203° C. (dec.).

Workup

  1. extractionThe mixture was extracted once with 1000 ml of methylene chloride and twice with 500 ml of methylene chloride each time
  2. dry with materialdried with MgSO4
  3. customThe residue, 14.6 g of brown oil, was chromatographed on 220 g of aluminium oxide (neutral, III) with methylene chloride as the eluent
  4. dissolution1.3 g of a total of 10.3 g of crude product were dissolved in a 25-fold amount of ethanol

Sources & evidence

ORD record
ord-cecf8fc6aec34dd2a08ec34e4a98948d
Source dataset
uspto-grants-1994_03
Patent number
US05292732

Reaction notes

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