Hydrochloric Acid → HCID 22712059, compound

HRID 352420Notes

Reaction equation

HRID 352420 reaction equation
[C:1]1(=[N:6][NH:7][C:8]([NH2:10])=S)[CH2:5][CH2:4][CH2:3][CH2:2]1.C(NC(C)C)(C)C.[Li].Cl.S.[OH-].[Na+]>O1CCCC1>[NH:6]1[C:1]2[CH2:5][CH2:4][CH2:3][C:2]=2[C:8]([NH2:10])=[N:7]1

Participants

7

Reactant 5

HCID 313Hydrochloric AcidHCID 402Hydrogen SulfideHCID 14798Sodium HydroxideHCID 6901022-Cyclopentylidenehydrazine-1-carboximidothioic acidHCID 45051747Lithium diisopropylamine

Product 1

HCID 22712059HCID 22712059, compoundYield 62.2%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

5.3 g of cyclopentanone thiosemicarbazone is carefully added at 0° C. to a solution of lithium diisopropylamine in 200 ml of tetrahydrofuran (from 29 ml of diisopropylamine and 81 ml of 1.6 M n-butyllithium), whereby the temperature rises to 30° C. Then, it is stirred for 2 hours at room temperature. Then, 150 ml of 4N hydrochloric acid is carefully added in drops (exothermic, H2S development), and the mixture is refluxed for 30 minutes. Then, it is cooled to 5° C. and set at pH 14 with sodium hydroxide solution. The aqueous phase is extracted three times with tetrahydrofuran/ethyl acetate 95:5. The crude product is purified by column chromatography on silica gel with 1 l of ethyl acetate and 1 l of ethyl acetate/methanol 9:1 with the addition of 3% triethylamine. 2.58 g of 1,4,5,6-tetrahydro-cyclopentapyrazol-3-yl-amine with a melting point of 116-120° C. is obtained.

Workup

  1. customrises to 30° C
  2. temperaturethe mixture is refluxed for 30 minutes
  3. temperatureThen, it is cooled to 5° C.
  4. extractionThe aqueous phase is extracted three times with tetrahydrofuran/ethyl acetate 95:5
  5. customThe crude product is purified by column chromatography on silica gel with 1 l of ethyl acetate and 1 l of ethyl acetate/methanol 9:1 with the addition of 3% triethylamine

Sources & evidence

ORD record
ord-afae7f681e3748d8ab9a8e2228a47be7
Source dataset
uspto-grants-2004_06
Patent number
US06747046B2

Reaction notes

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