Piperazine → 2-Piperazin-1-yl-1,3-benzothiazole

HRID 1720779Notes

Reaction equation

HRID 1720779 reaction equation
Cl[C:2]1[S:3][C:4]2[CH:10]=[CH:9][CH:8]=[CH:7][C:5]=2[N:6]=1.[NH:11]1[CH2:16][CH2:15][NH:14][CH2:13][CH2:12]1>>[N:11]1([C:2]2[S:3][C:4]3[CH:10]=[CH:9][CH:8]=[CH:7][C:5]=3[N:6]=2)[CH2:16][CH2:15][NH:14][CH2:13][CH2:12]1

Participants

3

Reactant 2

HCID 4837PiperazineHCID 119872-Chlorobenzothiazole

Product 1

HCID 5921222-Piperazin-1-yl-1,3-benzothiazole

Procedure

2-Chlorobenzothiazole (5.00 g), is heated in alcohol (75 ml) with 3.05 g piperazine (3.05 g) for 20 hr. 1% mixture is partitioned between methylene chloride/ether and aqueous sodium bicarbonate, the phases are separated, the organic phase is dried with sodium sulfate and concentrated to give 2-piperazinobenzothiazole which is reacted at 70° in acetonitrile (200 ml) with 21-bromo-17α-hydroxypregna-4,9(11)-diene-3,20-dione (7.45 g) and potassium carbonate (2.44 g) for 6 hr and at 20°-25° for 3 days. The mixture is partitioned between methylene chloride and aqueous sodium bicarbonate, the phases are separated, the organic phase is dried with sodium sulfate and concentrated. The concentrate is chromatographed on silica gel eluting with methanol/methylene chloride (6/94) to give the title compound which is recrystallized from ethyl acetate.

Workup

  1. custom1% mixture is partitioned between methylene chloride/ether and aqueous sodium bicarbonate
  2. customthe phases are separated
  3. dry with materialthe organic phase is dried with sodium sulfate
  4. concentrationconcentrated

Sources & evidence

ORD record
ord-93780d1f062942aaa597f48a0306e775
Source dataset
uspto-grants-1996_04
Patent number
US05506354

Reaction notes

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