Hydrochloric Acid → 2,4,5,6-Tetrahydrocyclopenta[c]pyrazol-3-amine

HRID 352420ノート

反応式

HRID 352420 の反応式
[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

参加物

7

反応物 5

HCID 313Hydrochloric AcidHCID 402Hydrogen SulfideHCID 14798Sodium HydroxideHCID 690102Cyclopentanone thiosemicarbazoneHCID 45051747Lithium diisopropylamine

生成物 1

HCID 227120592,4,5,6-Tetrahydrocyclopenta[c]pyrazol-3-amine収率 62.2%

試薬・触媒・溶媒 1

HCID 8028Tetrahydrofuran溶媒

実験手順

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.

後処理

  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

出典と根拠

ORDレコード
ord-afae7f681e3748d8ab9a8e2228a47be7
出典データセット
uspto-grants-2004_06
特許番号
US06747046B2

反応ノート

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