Stannous chloride dihydrate → HCID 67253832, compound

HRID 1711689Notes

Reaction equation

HRID 1711689 reaction equation
[NH2:1][C:2]1[CH:10]=[CH:9][C:5]2[N:6]=[CH:7][S:8][C:4]=2[CH:3]=1.[N:11]([O-])=O.[Na+].O.O.Cl[Sn]Cl.[CH3:20][CH:21]([CH3:27])[C:22](=O)[CH2:23][C:24]#[N:25]>Cl.O.CCO>[S:8]1[C:4]2[CH:3]=[C:2]([N:1]3[C:24]([NH2:25])=[CH:23][C:22]([CH:21]([CH3:27])[CH3:20])=[N:11]3)[CH:10]=[CH:9][C:5]=2[N:6]=[CH:7]1

Participants

8

Reactant 4

HCID 61436Stannous chloride dihydrateHCID 682886-AminobenzothiazoleHCID 101299214-Methyl-3-oxopentanenitrileHCID 23668193Sodium Nitrite

Product 1

HCID 67253832HCID 67253832, compoundYield 93%

Reagents, catalysts & solvents 3

HCID 313Hydrochloric AcidSolvent2×HCID 702EthanolSolventHCID 962WaterSolvent

Conditions

Temperature
2.5 °C

Procedure

To a stirring suspension of 6-aminobenzothiazole (0.500 g, 3.33 mmol) in conc. HCl (5 ml) at 0-5° C. was added a solution of NaNO2 (0.276 g, 3.99 mmol) in H2O (5 ml). The mixture was stirred at 0-5° C. for 75 min until a clear yellow solution was obtained. To this was then added a solution of SnCl2.2H2O (2.76 g, 13.3 mmol) in conc. HCl (5 ml). After completing the addition, the suspension was stirred at RT for 2 h. 4-Methyl-3-oxopentanenitrile (0.444 g, 3.99 mmol) and EtOH (50 ml) were added and the reaction was stirred with heating at 75° C. After 18 h, the completed reaction was cooled to RT and concentrated to an aqueous residue. This was chilled thoroughly in ice and made strongly basic (pH 12-13) by the addition of 6M NaOH. While still cold the mixture was extracted with EtOAc (2×). The combined organics were washed with H2O (2×), brine (1×), dried (MgSO4), filtered and evaporated to afford crude 1-(benzo[d]thiazol-6-yl)-3-isopropyl-1H-pyrazol-5-amine (0.8 g, 93% yield) as an oil which was used as is in the next reaction. 1H NMR (400 MHz, DMSO-d6) δ 9.36 (s, 1H), 8.30 (d, J=2.4 Hz, 1H); 8.10 (d, J=8.8 Hz, 1H), 7.74 (dd, J=2.4 and 8.8 Hz, 1H), 5.36 (s, 1H), 5.33 (brs, 2H), 2.76 (septet, J=6.8 Hz, 1H), 1.17 (d, J=6.8 Hz, 6H); MS (ESI) m/z: 259.0 (M+H+).

Workup

  1. customwas obtained
  2. additionthe addition
  3. stirringthe suspension was stirred at RT for 2 h
  4. stirringthe reaction was stirred
  5. temperaturewith heating at 75° C
  6. waitAfter 18 h
  7. customthe completed reaction
  8. temperaturewas cooled to RT
  9. concentrationconcentrated to an aqueous residue
  10. temperatureThis was chilled thoroughly in ice
  11. additionby the addition of 6M NaOH
  12. extractionWhile still cold the mixture was extracted with EtOAc (2×)
  13. washThe combined organics were washed with H2O (2×), brine (1×)
  14. dry with materialdried (MgSO4)
  15. filtrationfiltered
  16. customevaporated

Sources & evidence

ORD record
ord-2e91867d0b164df2a067e1754e9b6ac5
Source dataset
uspto-grants-2010_09
Patent number
US07790756B2

Reaction notes

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