Water → 9H-Indeno[1,2-b]pyrazine-2,3,9(1H, 4H)-trione 9-ethylene dithioacetal

HRID 129454

Reaction equation

HRID 129454 reaction equation
[NH:1]1[C:6](=O)[C:5](=[O:8])[NH:4][C:3]2[C:9]3[CH:10]=[CH:11][CH:12]=[CH:13][C:14]=3[C:15](=[O:16])[C:2]1=2.O.[CH2:18]([SH:21])[CH2:19][SH:20].B(F)(F)F.CCOCC>C1(C)C=CC=CC=1>[CH2:18]1[S:21][C:6]2([C:5](=[O:8])[NH:4][C:3]3[C:9]4[CH:10]=[CH:11][CH:12]=[CH:13][C:14]=4[C:15](=[O:16])[C:2]=3[NH:1]2)[S:20][CH2:19]1

Participants

6

Reactant 4

HCID 962WaterHCID 8000Boron trifluoride etherateHCID 109021,2-EthanedithiolHCID 190359779H-Indeno[1,2-b]pyrazine-2,3,9(1H,4H)-trione

Product 1

HCID 867491119H-Indeno[1,2-b]pyrazine-2,3,9(1H, 4H)-trione 9-ethylene dithioacetalYield 83%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

A suspension of 9H-indeno[1,2-b]pyrazine-2,3,9(1H, 4H)-trione. 0.9 H2O (2.0 g, 8.68 mmol) in toluene (50 ml), 1,2-ethanedithiol (2.19 ml, 26.04 mmol) and boron trifluoride etherate (1.07 ml, 8.68 mmol) was refluxed for 20 hours. The reaction mixture was cooled to room temperature, and the precipitate was filtered off and washed with toluene, ethanol-water (2:1) and ethanol. The crude material (2.40 g) was recrystallized from DMF-water to give 2.09 g (83%) of the title compound. M.p. >300° C. 1H-NMR (DMSO-d6, δ): 3.68 (m, 2H), 3.91 (m, 2H), 7.2 (t, 1H), 7.3 (t, 1H), 7.51 (d, 1H), 7.59 (d, 1H), 12.05 (s, 1H), 12.38 (s, 1H).

Workup

  1. filtrationthe precipitate was filtered off
  2. washwashed with toluene, ethanol-water (2:1) and ethanol
  3. customThe crude material (2.40 g) was recrystallized from DMF-water

Sources & evidence

ORD record
ord-e3791f7b9e7e4eae98cbd9f962e98b24
Source dataset
uspto-grants-1995_11
Patent number
US05468748

Linked notes

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