Aluminium lithium hydride → 3-Chloro-2-(hydroxymethyl)-6,7-dihydropyrazolo[1,5-a]pyrazin-4(5H)-one

HRID 2046232Notes

Reaction equation

HRID 2046232 reaction equation
[H-].[Al+3].[Li+].[H-].[H-].[H-].C([O:9][C:10]([C:12]1[C:21]([Cl:22])=[C:15]2[C:16](=[O:20])[NH:17][CH2:18][CH2:19][N:14]2[N:13]=1)=O)C>C1COCC1.CCOC(C)=O>[Cl:22][C:21]1[C:12]([CH2:10][OH:9])=[N:13][N:14]2[CH2:19][CH2:18][NH:17][C:16](=[O:20])[C:15]=12

Participants

5

Reactant 2

HCID 21226445Aluminium lithium hydrideHCID 679746013-Chloro-4-oxo-4,5,6,7-tetrahydro-pyrazolo[1,5-a]pyrazine-2-carboxylic acid ethyl ester

Product 1

HCID 679760143-Chloro-2-(hydroxymethyl)-6,7-dihydropyrazolo[1,5-a]pyrazin-4(5H)-oneYield 79%

Reagents, catalysts & solvents 2

HCID 8028TetrahydrofuranSolventHCID 8857Ethyl AcetateSolvent

Procedure

A 1M solution of lithium aluminum hydride was added to a stirred solution of 3-chloro-4-oxo-4,5,6,7-tetrahydro-pyrazolo[1,5-a]pyrazine-2-carboxylic acid ethyl ester (0.37 g, 1.51 mmol) in THF (15 mL) at 0° C. The mixture was stirred at room temperature for 2 hours and then diluted with AcOEt. Na2SO4.10H2O was added at 0° C. and the mixture stirred for 15 minutes at 0° C., filtered through a pad of diatomaceous earth and then washed with additional THF. The solvents were evaporated in vacuo to yield 3-chloro-2-hydroxymethyl-6,7-dihydro-5H-pyrazolo[1,5-a]pyrazin-4-one (0.24 g, 79% yield) that was used in the next step without further purification.

Workup

  1. stirringthe mixture stirred for 15 minutes at 0° C.
  2. filtrationfiltered through a pad of diatomaceous earth
  3. washwashed with additional THF
  4. customThe solvents were evaporated in vacuo

Sources & evidence

ORD record
ord-1dc9623bc115484d9596b7e36c4a6801
Source dataset
uspto-grants-2013_11
Patent number
US08592422B2

Reaction notes

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